{{Infobox Military Conflict
|conflict=Tet Offensive
|partof=the Vietnam War
|image=300px
|caption=Some of the major communist targets during the Tet Offensive
|date=30 January 1968 - 23 September 1968
|place=South Vietnam
|result=Allied military victory <br> Communist propaganda victory  
|combatant1=22px 22px 22px 22px 22px New Zealand
|combatant2=22px 22px North Vietnam
|commander1=William C. Westmoreland
|commander2=Võ Nguyên Giáp
|strength1=~1 million<ref name=Lung8>Hoang Ngoc Lung, ''The General Offensives'' McLean VA: General Research Corporation, 1978, p. 
8.</ref>
|strength2=~323,000 - 595,000<ref>The South Vietnamese estimated communist forces at 323,000, including 130,000 regulars and 160,000 guerrillas. Hoang, p. 10. MACV estimated that strength at 330,000. The CIA and the U.S. State Department concluded that the communist force level lay somewhere between 435,000 and 595,000. Clark Dougan & Stephen Weiss, ''Nineteen Sixty-Eight'', Boston: Boston Publishing Compnay, 1983, p. 184.</ref> 
|casualties1=22px<br>'''Phase I''': 2,788 killed, 8,299 wounded, 587 missing<br> '''Phase II''': 143 killed, 646 wounded<br> '''Phase III''': unknown<br> '''Civilian''': 14,000 killed, 24,000 wounded
22px22px22px 22px<br> '''Phase I''': 1,536 killed, 7,764 wounded, 11 missing<br> '''Phase II''': 1,161 killed, 3,954 wounded<br> '''Phase III''': 700 killed, wounded unknown<br> '''Total Allied military''':<br> 6,328 killed (approximate), 20,663 wounded (approximate), 1,185 missing<ref>Does not include ARVN or U.S. casualties incurred during the "Border Battles"; ARVN killed, wounded, or missing from Phase III; U.S. wounded from Phase III; or U.S. missing during Phases II and III.</ref>
|casualties2='''Total''': 85 - 100 thousand killed (estimate), wounded unknown<ref>Includes casualties incurred during the "Border Battles", Tet Mau Than, and the second and third phases of the offensive. General Tran Van Tra claimed that from January through August 1968 the offensive had cost the communists more than 75,000 dead and wounded. This is probably a low estimate. Tran Van Tra, ''Tet'', in Jayne S. Warner and Luu Doan Huynh, eds., ''The Vietnam War: Vietnamese and American Perspectives''. Armonk NY: M.E. Sharpe, 1993, pgs. 49 & 50.</ref>
|casualties3=Officially 14,300 civilians killed and 24,000 wounded
}}

The '''Tet Offensive''' was a military campaign conducted between 30 January and 23 September 1968, by communist forces of the National Front for the Liberation of South Vietnam (aka Viet Cong) and the People's Army of Vietnam (PAVN) against the forces of the Republic of Vietnam (South Vietnam), the United States (U.S.), and their allies during the Vietnam War. The purpose of the offensive was to strike military and civilian command and control centers throughout the South Vietnam and to spark a general uprising among the population that would then topple the Saigon government, thus ending the war in a single blow.<ref>

Ang Cheng Guan, "Decision-making Leading to the Tet Offensive," ''Journal of Contemporary History'' 33 (July 1998): 351. Two interpretations of communist goals have continued to dominate Western historical debate. The first maintained that the political consequences of the Winter-Spring Offensive were an intended rather than an unintended consequence. This view was supported by William Westmoreland in ''A Soldier Reports'', Garden City NY: Doubleday, 1976,p. 322; Harry G. Summers in ''On Strategy'', Novato CA: Presidio Press, 1982, p. 133; Leslie Gelb and Richard Betts, ''The Irony of Vietnam'', Washington DC: The Brookings Institute, 1979, pgs. 333 & 334; and Schmitz p. 90. This thesis appeared logical in hindsight, but it "fails to account for any realistic North Vietnamese military objectives, the logical prerequisite for an effort to influence American opinion." James J. Wirtz in ''The Tet Offensive'', Ithica NY: Cornell University Press, 1991, p. 18. The second thesis (which was also supported by the majority of contemporary captured Vietcong documents) was that the goal of the offensive was the immediate toppling of the Saigon government or, at the very least, the destruction of the government apparatus, the installation of a coalition government, or the occupation of large tracts of South Vietnamese territory. Historians supporting this view are Stanley Karnow in ''Vietnam'', New York: Viking, 1983, p. 537; U.S. Grant Sharp in ''Strategy for Defeat'', San Rafael CA: Presidio Press, 1978, p. 214; Patrick McGarvey in ''Visions of Victory'', Stanford CA: Stanford University Press, 1969; and Wirtz, p. 60.</ref>

The operations are referred to as the Tet Offensive because they began during the early morning hours of Tết Nguyên Đán'', which celebrates the first day of the year on a traditional lunar calendar. Both North and South Vietnam announced on national radio broadcasts that there would be a three-day cease-fire in honor of Tết. In Vietnamese, the episode is known as ''Tổng công kích, Tổng khởi nghĩa'' ("General Offensive and General Uprising") or ''(Xuân) Mậu Thân'' ("[Spring Offensive] Year of the Monkey"). 

For reasons that are still not completely understood, a wave of attacks began on the morning of 30 January in the I and II Corps Tactical Zones. This early attack did not, however, cause undue alarm or lead to widespread allied defensive measures. When the main communist operation began the next morning, the offensive was countrywide in scope and well coordinated, with more than 80,000 Vietcong troops striking more than 100 towns and cities, including 36 of 44 provincial capitals, five of the six autonomous cities, 72 of 245 district towns, and the national capital.<ref name=DouganWeiss8>Dougan & Weiss, p. 8.</ref> The offensive was the largest military operation yet conducted by either side up to that point in the war.

The initial NLF attacks stunned allied forces and took them by surprise, but most were quickly contained and beaten back, inflicting massive casualties on the communists. The exceptions were the fighting that erupted in the old imperial capital of Huế, where intense fighting lasted for a month, and the continuing struggle around the U.S. combat base at Khe Sanh, where fighting continued for two more months. Although the offensive was a military disaster for Vietcong forces, it had a profound effect on the American administration and shocked the American public, which had been led to believe by its political and military leaders that the communists were, due to previous defeats, incapable of launching such a massive effort. 

The majority of Western historians have concluded that the offensive ended in June, which easily located it within framework of U.S. political and military decisions that altered the American commitment to the war. In fact, the General Offensive continued, according to plan, through two more distinct phases. The second phase began on 5 May and continued until the end of the month. The third began on 17 August and only ended on 23 September.

==Light at the end of the tunnel<ref>Although General Westmoreland never uttered this phrase (it was coined by General Henri Navarre during the First Indochina War), it came into general parlance during the Vietnam War and has become a catchphrase for similar situations.</ref>==
===Order of battle and communist capabilities===

During the fall of 1967, two questions weighed heavily on the minds of the American public and the administration of President Lyndon B. Johnson: Was the U.S. strategy of attrition working in Vietnam and who was winning the war? According to General William C. Westmoreland, the commander of the Military Assistance Command, Vietnam (MACV), the answer could be found by the solution to a simple equation. Take the total number of communist troops estimated incountry and subtract those killed or captured during military operations to determine the "crossover point" at which the number of those eliminated exceeded those recruited or replaced. There was a discrepancy, however, between MACV and the Central Intelligence Agency's (CIA) order of battle estimates concerning the strength of communist guerrilla forces within South Vietnam.<ref>Clark Dougan and Stphen Weiss, Nineteen Sixty-Eight (Boston Publishing Company), 22-23</ref> In September, members of the MACV intelligence services and the CIA met to prepare a Special National Intelligence Estimate that would be utilized by the administration as a gauge of U.S. success in the conflict.
thumbnail|left|175px|General William C. Westmoreland, [[COMUSMACV]]
Provided with an enemy intelligence windfall accrued during Operations ''Cedar Falls'' and ''Junction City'', the CIA members of the group believed that the number of communist  guerrillas, irregulars, and cadre within the South could be as high as 430,000. The MACV Combined Intelligence Center, on the other hand, maintained that the number could be no more than 300,000.<ref name=DouganWeiss22>Dougan & Weiss, p. 22.</ref> Westmoreland was deeply concerned about the possible perceptions of the American public to such an increased estimate, since Vietcong troop strength was routinely provided to reporters during press briefings.<ref>William H. Hammond, ''The Military and the Media, 1962-1968''. Washington DC: U.S. Army Center of Military History, 1988. 
Hammond, p. 326.</ref> According to MACV's chief intelligence, General Joseph McChristian, the new figures "would create a political bombshell," since they were proof positive that the communists "had the capability and the will to continue a protracted war of attrition."<ref name=DouganWeiss22>Dougan & Weiss, p. 22.</ref>

In May, MACV attempted to obtain a compromise from the CIA by maintaining that Vietcong militias did not constitute a fighting force but were essentially low level fifth columnists used for information collection.<ref>Dougan & Weiss, p. 23.</ref> The agency responded that such a notion was ridiculous, since the militias were directly responsible for half of the casualties inflicted on U.S. forces. With both groups in deadlock, George Carver, CIA deputy director for Vietnamese affairs, was asked to mediate the dispute. In September, Carver devised a compromise: The CIA would drop its insistence on including the irregulars in the final tally of forces and add a prose addendum to the estimate that would explain the agency's position.<ref>Hammond, pgs. 326 & 327.</ref> George Allen, Carver's deputy, laid responsibility for the agency's capitulation at the feet of Richard Helms, the director of the CIA. He believed that "it was a political problem...[Helms] didn't want the agency...contravening the policy interest of the administration."<ref name=DouganWeiss>Dougan & Weiss, p. 23. This Order of Battle controversy resurfaced in 1982, when Westmoreland filed a lawsuit against CBS News after the airing of its program, ''The Uncounted Enemy: A Vietnam Deception'', which aired had on 23 January 1982.</ref>

===Successes Offensive===
During the second half of 1967 the administration had become alarmed by criticism, both inside and outside the government, and by reports of declining public support for its Vietnam policies.<ref>Those in the administration and the military who urged a change in strategy included: Secretary of Defense Robert S. McNamara; Undersecretary of State Nicholas Katzenbach; Assistant Secretary for Far Eastern Affairs William Bundy; Ambassador to South Vietnam Henry Cabot Lodge; General Creighton W. Abrams, deputy commander of MACV; and Lieutenant General Frederick C. Weyand, commander of II Field Force, Vietnam. Lewis Sorley, ''A Better War''. New York: Harvest Books, 1999, p. 6. Throughout the year, the ''Pentagon Papers'' claimed, Johnson had discounted  any "negative analysis" of U.S. strategy by the CIA and the Pentagon offices of International Security Affairs and System Analysis, and had instead "seized upon optimistic reports from General Westmoreland." Neil Sheehan, et al. ''The Pentagon Papers as Reported by the New York Times''. New York: Ballentine, 1971, p. 592.</ref> According to public opinion polls, the percentage of Americans who believed that the U.S. had made a mistake by sending troops to Vietnam had risen from 25 percent in 1965 to 45 percent by December 1967.<ref name=DouganWeiss68>Dougan & Weiss, p. 68.</ref> This trend was fueled not by a belief that the struggle was not worthwhile, but by mounting casualty figures, rising taxes, and the feeling that there was no end to the war in sight.<ref>Stanley Karnow, ''Vietnam''. New York: Viking, 1983, p. 545 & 546.</ref> A poll taken in November indicated that 55 percent wanted a tougher war policy, exemplifing the public belief that "it was an error for us to have gotten involved in Vietnam in the first place. But now that we're there, let's win - or get out."<ref name=Karnow546>Karnow, p. 546.</ref> This prompted the administration to launch a so-called "Success Offensive", a concerted effort to alter the widespread public perception that the war had reached a stalemate and to convince the American people that the administration's policies were succeeding. Under the leadership of National Security Advisor Walt W. Rostow, the news media then was inundated by a wave of effusive optimism.
<!-- Unsourced image removed: thumb|right|200px|President Lyndon B. Johnson in consultation with General Earl G. Wheeler, chairman of the Joint Chiefs of Staff -->
Every statistical indicator of progress, from "kill ratios" and "body counts" to village pacification was fed to the press and to the Congress. "We are beginning to win this struggle" asserted Vice President Hubert H. Humphrey on NBC's "Today Show" in mid-November. "We are on the offensive. Territory is being gained. We are making steady progress."<ref name=DouganWeiss66>Dougan & Weiss, p. 66.</ref> At the end of November, the campaign reached its climax when Johnson summoned Westmoreland and the new U.S. Ambassador, Ellsworth Bunker, to Washington, D.C., for what was billed as a "high level policy review". Upon their arrival, the two men bolstered the administration's claims of success. From Saigon, pacification chief Robert Komer asserted that the pacification program in the countryside was succeeding. Sixty-eight percent of the South Vietnamese population was under the control of Saigon while only seventeen percent was under the control of the Vietcong.<ref name=Schmitz56>Schmitz, p. 56.</ref> General Bruce Palmer, one of Westmoreland's three Field Force commanders, claimed that "the Viet Cong has been defeated" and that "He can't get food and he can't recruit. He has been forced to change his strategy from trying to control the people on the coast to trying to survive in the mountains."<ref name=Schmitz58>Schmitz, p. 58.</ref> 

Westmoreland was even more emphatic in his assertions. At an address at the National Press Club on 21 November he reported that, as of the end of 1967, the Vietcong was "unable to mount a major offensive...I am absolutely certain that whereas in 1965 the enemy was winning, today he is certainly losing...We have reached an important point when the end begins to come into view."<ref name=DouganWeiss66>Dougan & Weiss, p. 66.</ref> By the end of the year the administration's approval rating had indeed crept up by eight percent, but an early January Gallup poll indicated that forty-seven percent of the American public still disapproved of the President's handling of the war.<ref name=DouganWeiss69>Dougan & Weiss, p. 69.</ref> The American public, "more confused than convinced, more doubtful than despairing...adopted a 'wait and see' attitude."<ref name=DouganWeiss67>Dougan & Weiss, p. 67.</ref> During a discussion with an interviewer from Time magazine, Westmoreland defied the communists to launch an attack: "I hope they try something, because we are looking for a fight."<ref name=Karnow514>Karnow, p. 514.</ref>

===Northern decisions===
====Party politics====
Planning in Hanoi for a winter-spring offensive during 1968 had begun in early 1967 and continued until early the following year. There has been an extreme reluctance among communist historians to discuss the decision-making process that led to the ''General Offensive General Uprising'', even decades after the event.<ref>David Elliot, ''The Vietnamese War'', Vol. 2, Armonk NY: M.E. Sharpe, 2003, p. 1055.</ref> In official North Vietnamese literature, the decision to launch ''Tet Mau Than'' was usually presented as the result of a perceived U.S. failure to win the war quickly, the failure of the American bombing campaign against the Democratic Republic of Vietnam (North Vietnam), and the anti-war sentiment that pervaded the population of the U.S.<ref>Lien Hang T. Nguyen, ''The War Politburo'' in ''Journal of Vietnamese Studies''. Vol. 1, Numbers 1 & 2, p. 4.</ref> The decision to launch the general offensive, however, was much more complicated. 

The decision signaled the end of a bitter, decade-long debate within the Party leadership between first two, and then three factions. The moderates believed that the economic viability of North Vietnam should come before support of a massive and conventional southern war and who generally followed the Soviet line of peaceful coexistence by reunifying Vietnam through political means. Heading this faction were party theoritician Trường Chinh and Minister of Defense Võ Nguyên Giáp. The militants, on the other hand, tended to follow the foreign policy line of the Peoples Republic of China and stridently called for the reunification of the nation by military means and that no negotiations should be undertaken with the Americans. This group was led by the "brothers Le" - Party First Secretary Lê Duẩn and Lê Ðức Thọ. From the early to mid-1960s, the militants had dictated the direction of the war in South Vietnam.<ref>Nguyen, pgs. 15 & 16.</ref>
<!-- Unsourced image removed: thumbnail|left|175px|General Nguyen Chi Thanh -->
General Nguyễn Chí Thanh the head of COSVN (the headquarters which controlled the war effort in the South), political commissar and commander-in-chief of the NLF forces in South Vietnam, was another prominent militant. Strangely, the followers of the Chinese line centered their strategy against the allies on large-scale, main force actions rather than the protracted guerrilla war espoused by Mao Zedong. Under Thanh's command, the North Vietnamese had matched the American military escalation in the South tit-for-tat.<ref name=Nguyen20>Nguyen, p. 20. See also Wirtz, pgs. 30-50.</ref>

By 1966-1967, however, after the infliction of massive casualties by the allies, stalemate on the battlefield, and destruction of the northern economy by U.S. air power, there was a dawning realization that, if current trends continued, Hanoi would eventually lack the resources necessary to affect the military situation in the South.<ref>Wirtz, p. 20.</ref> As a result, there were more strident calls by the moderates for negotiations and a revision of strategy. They felt that a return to guerrilla tactics was more appropriate since the U.S. could not be defeated conventionally. They also complained that the policy of rejecting negotiations was in error.<ref>Edward Doyle, Samuel Lipsman, & Terrence Maitland, ''The North''. Boston: Boston Publishing Company, 1986, p. 55.</ref> The Americans could only be worn down in a war of wills during a period of "fighting while talking." During 1967 things had become so bad on the battlefield that Lê Duẩn ordered Thanh to incorporate aspects of protracted guerrilla warfare into his strategy.<ref name=Nguyen22>Nguyen, p. 22.</ref> 

During the same period, a counterattack was launched by a new, third grouping (the centrists) led by Party Chairman Hồ Chí Minh, Lê Ðức Thọ, and Foreign Minister Nguyễn Duy Trinh, who called for negotiations.<ref>Contrary to Western belief, Hồ Chí Minh had been sidelined politically since 1963 and took little part in the day-to-day policy decisions of the Politburo or Secretariat. Nguyen, p. 30.</ref> From October 1966 through April 1967, a very public debate over military strategy took place in print and via radio between Thanh and his rival for military power, Giáp.<ref>Wirtz, pgs. 36-40 & 47-49.</ref> Giáp had advocated a defensive, primarily guerrilla strategy against the U.S. and South Vietnam.<ref>Hoang, pgs. 15 & 16. See also Doyle, Lipsman, & Maitland, p. 56.</ref> Thanh's position was that Giáp and his adherents were centered on their experiences during the First Indochina War and that they were too "conservative and captive to old methods and past experience... mechanically repeating the past."<ref name=Hoang16>Hoang, p. 16.</ref>

The arguments over domestic and military strategy also carried a foreign policy element as well, because North Vietnam was totally dependent on outside military and economic aid. The vast majority of its military equipment was provided by either the Soviet Union or the People's Republic. Beijing advocated that North Vietnam conduct a protracted war on the Maoist model, fearing that a conventional conflict might draw them in as it had in Korea. They also resisted the idea of negotiating with the allies. Moscow, on the other hand, advocated negotiations, but simultaneously armed Hanoi's forces to conduct a conventional war on the Soviet model. North Vietnamese politics, therefore consisted of maintaining a critical balance between war policy, internal and external policies, domestic adversaries, and foreign allies with "self-serving agendas."<ref>Nguyen, pgs. 18-20.</ref>
 
To "break the will of their domestic opponents and reaffirm their autonomy vis-a-vis their foreign allies" hundreds of pro-Soviet, party moderates, military officers, and intelligentsia were arrested on 27 July 1967, during what came to be called the Revisionist Anti-Party Affair.<ref name=Nguyen24>Nguyen, p. 24.</ref> All of the arrests were based on the individual's stance on the Politburo's choice of tactics and strategy for the proposed General Offensive.<ref name=Nguyen27>Nguyen, p. 27.</ref> This move cemented the position of the militants as Hanoi's strategy: The rejection of negotiations, the abandonment of protracted warfare, and the focus on the ''General Offensive, General Uprising'' in the towns and cities of South Vietnam. More arrests followed in November and December.

====General Offensive, General Uprising==== 
The operational plan for the ''General Offensive, General Uprising'' had its origin as the "COSVN proposal" at Thanh's southern headquarters in April 1967 and had then been relayed to Hanoi the following month. The general was then ordered to the capital to explain his concept in person to the Military Central Commission. At a meeting in July, Thanh briefed the plan to the Politburo.<ref>Military History Institute of Vietnam, ''Victory in Vietnam''. Trans. by Merle Pribbenow. Lawrence KS: University Press of Kansas, 2005, p. 371.</ref> On the evening of 6 July, after being given permission to begin preparations for the offensive, Thanh attended a party and died of a heart attack after having drunk too much.<ref>''Victory in Vietnam'', p. 380. For years Western historians believed that Thanh had died as a result of wounds received during a U.S. air raid. Nguyen, fn. 147 </ref>

After cementing their position during the Party crackdown, the militants sped up planning for a major conventional offensive to break the military deadlock. They concluded that the Saigon government and the U.S. presence were so unpopular with the population of the South that a broad-based attack would spark a spontaneous uprising of the population, which, if the offensive was successful, would enable the communists to sweep to a quick, decisive victory. Their basis for this conclusion included: a belief that the South Vietnamese military was no longer combat effective; the results of the fall 1967 South Vietnamese presidential election (in which the Nguyễn Văn Thiệu/Nguyễn Cao Kỳ ticket had only received 24 percent of the popular vote); the Buddhist Uprisings of 1963 and 1966; well-publicized anti-war demonstrations in Saigon; and continuous criticism of the Thieu government in the southern press.<ref>Hoang, p. 24.</ref> Launching such an offensive would also finally put an end to what have been described as "dovish calls for talks, criticism of military strategy, Chinese diatribes of Soviet perfidy, and Soviet pressure to negotiate - all of which needed to be silenced."<ref name=Nguyen24>Nguyen, p. 24.</ref> 
thumbnail|right|175px|[[North Vietnamese Army|North Vietnamese Defense Minister Võ Nguyên Giáp]]
In October, the Politburo decided on the Tet holiday as the launch date and met again in December to reaffirm its decision and formalize it at the 14th Plenary session of the Party Central Committee in January 1968.<ref>Ang Cheng Guan, ''Decision-making Leading to the Tet Offensive'', in ''Journal of Contemporary History'', vol. 33, July 1998, p. 352.</ref> The resultant ''Resolution 14'' was a major blow to domestic opposition and "foreign obstruction." Concessions had been made to the center group, however, by agreeing that negotiations were possible, but the document essentially centered on the creation of "a spontaneous uprising in order to win a decisive victory in the shortest time possible."<ref>Doyle, Lipsman, & Maitland, p. 56.</ref> 

Contrary to Western belief, General Giáp did not plan the offensive himself. Thanh's original plan was elaborated on by a party committee headed by Thanh's deputy, Phạm Hùng, and then modified by Giáp.<ref>Nguyen, p. 34. William J. Duiker, ''Communist Road to Power''. Boulder CO: Westview Press, 1996, p. 288. Also see Doyle, Lipsman, & Maitland, p. 56.</ref> The Defense Minister may have been convinced to toe the line by the arrest and imprisonment of most of the members of his staff during the Revisionist Anti-Party Affair. Although Giáp went to work "reluctantly, under duress," he may have found the task easier due to the fact that he was faced with a ''fait accompli''.<ref>Marc J. Gilbert & James Wells ''Hau Nghia Part 3'', 2005. http://grunt.space.swri.edu/gilbert3.htm. This reference, left over from an earlier editor, is a fine example of just how discerning research has to be. One of the few accurate statements in it is the one quoted above. The rest is inaccurate gibberish.</ref> Since the Politburo had already approved the offensive, all he had to do was make it work. He combined guerrilla operations into what was basically a conventional military offensive and shifted the burden of sparking the popular uprising to the Vietcong. If it worked, all would be well and good. If it failed, it would be a failure only for the Party militants. For the moderates and centrists it offered the prospect of negotiations and a possible end to the American bombing of the North. Only in the eyes of the militants, therefore, did the offensive become a "go for broke" effort. Others in the Politburo were willing to settle for a much less ambitious "victory."<ref>Doyle, Lipsman, & Maitland, pgs. 58 & 59.</ref>

The operation would involve a preliminary phase during which diversionary attacks would be launched in the border areas of South Vietnam to draw American attention and forces away from the cities. The ''General Offensive, General Uprising'' would then proceed by launching simultaneous actions in most of the urban areas of South Vietnam and attacks on major allied bases, with particular emphasis focused on the cities of Saigon and Hue. Concurrently, a substantial threat would to be made against the U.S. combat base at Khe Sanh. The Khe Sanh actions would draw North Vietnamese forces away from the offensive into the cities, but Giáp considered them necessary in order to protect his supply lines and divert American attention.<ref name=Duiker299>Duiker, p. 299.</ref> Attacks on other U.S. forces were of secondary, or even tertiary importance, since Giáp considered his main objective to be weakening or destroying the South Vietnamese military and government through popular revolt.<ref name=Hoang26>Hoang, p. 26.</ref> The offensive, therefore was aimed at convincing the South Vietnamese public, not that of the U.S. There is conflicting evidence as to whether, or to what extent, the offensive was intended to influence either the March primaries or the November presidential election in the U.S.<ref> Hoang offered opposing viewpoints (pgs. 22 & 23) while William Duiker (p. 289) and Clark Clifford (p. 475) believed that it was so intended. Stanley Karnow did not (p. 537), while William Westmoreland never even mentioned the prospect in his memoir. A study of North Vietnamese documentation by James Wirtz led him to conclude that Giáp believed that the American people would have to be exposed to two more years of military stalemate (post the offensive) before they would be turned decisively against the war. Wirtz, p. 61.</ref>
thumb|left|200px|Vietcong troops pose with new AK-47 assault rifles and American field radios
According to General Trần Văn Trà, the new military head of COSVN, the offensive was to have three distinct phases: Phase I, scheduled to begin on 31 January, was to be a country-wide assault on the cities conducted primarily by Vietcong forces. Concurrently, a propaganda offensive to enduce ARVN troops to desert and the South Vietnamese population to rise up against the government would be launched. If outright victory was not achieved, the battle might still lead to the creation of a coalition government and the withdrawal of the Americans. If the general offensive failed to achieve these purposes, followup operations would be conducted to wear down the enemy and lead to a negotiated settlement; Phase II was scheduled to begin on 5 May; and Phase III on 17 August.<ref>Trần Văn Trà, ''Tet'', p. 40. </ref>

Preparations for the offensive were already underway. The logistical build-up began in mid-year, and by January 1968, 81,000 tons of supplies and 200,000 troops, including seven complete infantry regiments and 20 independent battalions made the trip south on the B-40 rocket-propelled grenade launchers, which granted them superior firepower over their less well-armed ARVN opponents. To pave the way and to confuse the allies as to its intentions, Hanoi launched a diplomatic offensive. Foreign Minister Trinh announced on 30 December that Hanoi ''would'' rather than ''could'' open negotiations if the U.S. unconditionally ended Operation ''Rolling Thunder'', the bombing campaign against North Vietnam.<ref name=DouganWeiss10>Dougan & Weiss, p. 10.</ref> This announcement provoked a flurry of diplomatic activity (which amounted to nothing) during the last weeks of the year. 

South Vietnamese and U.S. military intelligence estimated that North Vietnamese in South Vietnam during January 1968 totaled 323,000 men, including 130,000 North Vietnamese regulars, 160,000 NLF guerillas and members of the infrastructure, and 33,000 service and support troops. They were organized into nine divisions composed of 35 infantry and 20 artillery or anti-aircraft artillery regiments, which were, in turn, composed of 230 infantry and six sapper battalions.<ref name=Hoang10>Hoang, p. 10.</ref>

===Allied unpreparedness===
====Suspicions and diversions====
Signs of impending communist action did not go unnoticed among the allied intelligence collection apparatus in Saigon. During the late summer and fall of 1967 both South Vietnamese and U.S. intelligence agencies collected clues that indicated a significant shift in communist strategic planning. By mid-December, mounting evidence convinced many in Washington and Saigon that something big was underway. During the last three months of the year intelligence agencies had observed signs of a major communist military buildup. In addition to captured documents (a copy of ''Resolution 13'', for example, was captured by early October), observations of enemy logistical operations were also quite clear: in October the number of trucks observed heading south through Laos on the Hồ Chí Minh Trail jumped from the previous monthly average of 480 to 1,116. By November this total reached 3,823 and, in December, 6,315.<ref>Steven Hayward, ''The Tet Offensive: Dialogues'', April 2004. http://www.ashbrook.org/publicat/dialogue/hayward-tet.html#2r</ref> On 20 December Westmoreland cabled Washington that he expected the Vietcong "to undertake an intensified countrywide effort, perhaps a maximum effort, over a relatively short period of time."<ref name=DouganWeiss11>Dougan & Weiss, p. 11.</ref> 
thumbnail|right|150px|[[U.S.A. Lieutenant General Frederick C. Weyand, commander of II Field Force, Vietnam]]
Despite all the warning signs, however, the allies were still surprised by the scale and scope of the offensive. According to ARVN Colonel Hoang Ngoc Lung the answer lay with the allied intelligence methodology itself, which tended to estimate the Vietcong's probable course of action based upon their capabilities, not their intentions. Since, in the allied estimation, the Vietcong hardly had the capability to launch such an ambitious enterprise: "There was little possibility that the enemy could initiate a general offensive, regardless of his intentions."<ref>Hoang, p. 39.</ref> The answer could also be partially explained by the lack of coordination and cooperation between competing intelligence branches, both South Vietnamese and American. The situation from the U.S. perspective was best summed up by an MACV intelligence analyst: "If we'd gotten the whole battle plan, it wouldn't have been believed. It wouldn't have been credible to us."<ref>Dougan & Weiss, p. 11. The Tet Offensive would later be utilized in a textbook at West Point as an example of "an allied intelligence failure to rank with Pearl Harbor in 1941 or the Ardennes Offensive in 1944." Lieutenant Colonel Dave R. Palmer: ''Current Readings in Military History''. Clifford, p. 460.
</ref>  

From spring through the fall of 1967, the U.S. command in Saigon was perplexed by a series of actions initiated by the North Vietnamese and the Vietcong in the border regions. On 24 April a U.S. Marine Corps patrol prematurely triggered a North Vietnamese offensive aimed at taking the airstrip and combat base at Khe Sanh, the western anchor of the Marine's defensive positions in Quang Tri Province. By the time the action there had ended in May, 940 North Vietnamese troops and 155 Marines had been killed.<ref name=Shore17>Moyars Shore, ''The Battle of Khe Sanh''. U.S. Marine Corps Historical Branch, 1969, p. 17.</ref> For 49 days during early September and lasting into October, the North Vietnamese began shelling the U.S. Marine outpost of Con Thien, just south of the Demilitarized Zone or DMZ. The intense shelling (100-150 rounds per day) prompted Westmoreland to launch Operation ''Neutralize'', an intense aerial bombardment campaign of 4,000 sorties into and just north of the demarcation line.<ref>John Morocco, ''Thunder from Above''. Boston: Boston Publishing Company, 1984, pgs. 174-176.</ref> 

On U.S. 1st Infantry Division and the ARVN 18th Division and left 800 North Vietnamese troops dead at its conclusion.<ref name=Hoang9>Hoang, p. 9.</ref> 
<!-- Unsourced image removed: thumb|left|200px|U.S. troops pinned down during the fighting around DaK To -->
The most severe of what came to be known as "the Border Battles" erupted during October and November around Dak To, another border outpost in Kontum Province. The clashes there between the four regiments of the 1st North Vietnamese Division, the U.S. 4th Infantry Division, the U.S. 173rd Airborne Brigade, and ARVN infantry and Airborne elements, lasted for 22 days. By the time the fighting was over, between 1,200 and 1,600 North Vietnamese and 262 U.S. troops had lost their lives.<ref name=Hoang9>Hoang, p. 9.</ref> MACV intelligence was confused by the possible motives of the North Vietnamese in prompting such large-scale actions in remote regions where U.S. firepower and aerial might could be applied indiscriminately. Tactically and strategically, these operations made no sense. What the Vietcong had done was carry out the first stage of their plan: to fix the attention of the U.S. command on the borders and draw the bulk of U.S. forces away from the heavily populated coastal lowlands and cities.<ref>Terrence Maitland & Peter McInerney, ''A Contagion of War''. Boston: Boston Publishing Company, 1983, pgs. 160-183.</ref> 

Westmoreland was more concerned with the situation at Khe Sanh, where, on 21 January, a force estimated at between 20,000-40,000 North Vietnamese troops had besieged the U.S. Marine garrison. MACV was convinced that the communists planned to stage an attack and overrun the base as a prelude to an all-out effort to seize the two northernmost provinces of South Vietnam.<ref>Dave R. Palmer, ''Summons of the Trumpet''. New York: Ballentine, 1978, pgs. 229 & 233.</ref> To deter any such possibility, he deployed 250,000 men, including half of MACV's U.S. maneuver battalions, to the I Corps Tactical Zone. 

This course of events disturbed Lieutenant General Frederick C. Weyand, commander of U.S. forces in II Corps, which included the Capital Military District. Weyand, a former intelligence officer, was suspicious of the pattern of communist activities in his area of responsibility and notified Westmoreland of his concerns on 10 January. Westmoreland agreed with his estimate and ordered 15 U.S. battalions to redeploy from positions near the Cambodian border back to the outskirts of Saigon.<ref name=DouganWeiss8>Dougan & Weiss, p. 8.</ref> When the offensive did begin, a total of 27 allied maneuver battalions defended the city and the surrounding area. This redeployment may have been one of the most critical tactical decisions of the war.<ref name=Palmer235>Palmer, p. 235.</ref>

====Before the storm====
By the beginning of January 1968, the U.S had deployed 331,098 Army personnel and 78,013 Marines in nine divisions, an armoured cavalry regiment, and two separate brigades to South Vietnam. They were joined there by the 1st Australian Task Force, a Royal Thai Army regiment, two Republic of Korea infantry divisions, and a Korean Marine Corps brigade.<ref name=Stanton195>Shelby L. Stanton, ''Rise and Fall of an American Army''. New York: Dell, 1985, p. 195.</ref> South Vietnamese strength totaled 350,000 regulars in the Army, Air Force, Navy, and Marine Corps.<ref name=DouganWeiss124>Dougan & Weiss, p. 124.</ref> They were in turn supported by the 151,000-man Regional Forces and 149,000-man Popular Forces, which were the equivalent of regional and local militias.<ref name=Willbanks7>James H. Willbanks, ''The Tet Offensive'' New Haven CT: Yale University Press, 2006, p. 7.</ref>
thumbnail|left|250px|South Vietnam, Corps Tactical Zones
In the days immediately preceding the offensive, the preparedness of allied forces was relatively relaxed. North Vietnam had announced in October that it would observe a seven-day truce from 27 January to 3 February in honor of the Tet holiday, and the South Vietnamese military made plans to allow recreational leave for approximately one-half of its forces. General Westmoreland, who had already cancelled the truce in I Corps, requested that its ally cancel the upcoming cease-fire, but President Thieu (who had already reduced the cease-fire to 36 hours), refused to do so, claiming that it would damage troop morale and only benefit communist propagandists.<ref name=DouganWeiss12>Dougan & Weiss, p. 12.</ref> 

On 28 January 11 NLF cadre were captured in the city of Qui Nhon while in possession of two pre-recorded audio tapes whose message appealed to the populace in "already occupied Saigon, Hue, and Da Nang."<ref name=Hoang35>Hoang, p. 35.</ref> The following afternoon, General Cao Van Vien, chief of the ARVN General Staff, ordered his four corps commanders to place their troops on alert. Yet, there was still a lack of a sense of urgency on the part of the allies. If Westmoreland had a grasp of the potential for danger, he did not communicate it very well to others.<ref>In their memoirs, both Johnson and Westmoreland stated that they had predicted the offensive. According to Clark Clifford, however, these later claims were rather "self serving". Clark Clifford, with Richard Holbrooke, ''Counsel to the President''. New York: Random House, 1991, pgs. 467 & 468.</ref> On the evening of 30 January 200 U.S. colonels, all of whom served on the MACV intelligence staff, attended a pool party at the officer's quarters in Saigon. According to James Meecham, an analyst at the Combined Intelligence Center who attended the party: "I had no conception Tet was coming, absolutely zero... Of the 200-odd colonels present, not one I talked to knew Tet was coming, without exception."<ref name=Zaffiri280>Samuel Zaffiri, ''Westmoreland''. New York,: William Morrow, 1994, p. 280.</ref> 

The general also failed to communicate his concerns adequately to Washington. Although he had warned the President between 25 and 30 January that "widespread" Vietcong attacks were in the offing, his admonitions had tended to be so oblique or so hedged with official optimism that even the administration was unprepared.<ref name=Hammond342>Hammond, p. 342.</ref><ref name=Zaffiri280>s Zaffiri, p. 280.</ref> <ref>For a treatment of official statements predicting the offensive, see Peter Braestrup. ''Big Story'', New Haven CT: Yale University Press, 1983, 1:60-77.</ref> No one - in either Washington or Vietnam - was expecting what happened.

==Offensive==
==="Crack the Sky, Shake the Earth"<ref>Message to Vietcong forces who were informed that they were "about to inaugurate the greatest battle in the history of our country". Dougan & Weiss, p. 10.</ref>===
Whether by accident or design, the first wave of attacks began shortly after midnight on 30 January as all five provincial capitals in II Corps and Da Nang, in I Corps, were attacked.<ref>The first attacks may have been launched prematurely due to confusion over a changeover in the calendar date by NLF units. Hanoi had arbitrarily forwarded the date of the holiday in order to allow its citizens respite from the retaliatory airstrikes that were sure to follow the offensive. Whether this was connected to the mixup over the launch date is unknown. All eight of the attacks were controlled by the North Vietnamese headquarters of Military Region 5.</ref> Nha Trang, headquarters of the U.S. I Field Force, was the first to be hit, followed shortly by Ban Me Thuot, Kontum, Hoi An, Tuy Hoa, Da Nang, Qui Nhon, and Pleiku. During all of these operations, the NLF followed a similar pattern: mortar and/or rocket attacks were closely followed by massed ground assaults conducted by battalion-strength elements of the NLF (sometimes supported by North Vietnamese regulars). These forces would join with local cadres who served as guides to lead the regulars to the most senior South Vietnamese headquarters and the radio station. The operations, however, were not well coordinated at the local level and, by daylight, almost all communist forces had been driven from their objectives. General Phillip B. Davidson, the new MACV chief of intelligence, notified Westmoreland that "This is going to happen in the rest of the country tonight and tomorrow morning."<ref>William C. Westmoreland, ''A Soldier Reports''. New York: Doubleday, 1976, p. 323.</ref> All U.S. forces were placed on maximum alert and similar orders were issued to all ARVN units. The allies, however, still responded without any real sense of urgency. Orders cancelling leaves either came too late or were disregarded.<ref>Stanton, p. 209.</ref>
thumb|right|250px|U.S. Marines battle in Hamo village
At 03:00 on the morning of 31 January communist forces assailed Saigon, Cholon, and Gia Dinh in the Capital Military District; Quang Tri (again), Hue, Quang Tin, Tam Ky, and Quang Ngai as well as U.S. bases at Phu Bai and Chu Lai in I Corps; Phan Thiet, Tuy Hoa, and U.S. installations at Bong Son and An Khe in II Corps; and Can Tho and Vinh Long in IV Corps. The following day, Bien Hoa, Long Thanh, Binh Duong in III Corps and Kien Hoa, Dinh Tuong, Go Cong, Kien Giang, Vinh Binh, Ben Tre, and Kien Tuong in IV Corps were assaulted. The last attack of the initial operation was launched against Bac Lieu in IV Corps on 10 February. A total of approximately 84,000 Vietcong troops participated in the attacks while thousands of others stood by to act as reinforcements or as blocking forces.<ref>Westmoreland, p. 328. Palmer gave a figure of 70,000, p. 238.</ref> Communist forces also mortared or rocketed every major allied airfield and attacked 64 district capitals and scores of smaller towns. 

In most cases the defense against the ''General Offensive, General Uprising'' was a South Vietnamese affair. Local militia or ARVN forces, supported by the National Police, usually drove the attackers out within two or three days, sometimes within hours; but heavy fighting continued several days longer in Kontum, Ban Me Thuot, Phan Thiet, Can Tho, and Ben Tre.<ref>Westmoreland, p. 328.</ref> The outcome in each instance was usually dictated by the ability of local commanders - some were outstanding, some were cowardly and/or incompetent. During this crucial crisis, however, no South Vietnamese unit had been broken or had defected to the Vietcong.<ref name=Westmoreland332>Westmoreland, p. 332.</ref>

According to Westmoreland, he responded to the news of the attacks with optimism, both in media presentations and in his reports to Washington. According to closer observers, however, the general was "stunned that the communists had been able to coordinate so many attacks in such secrecy" and he was "dispirited and deeply shaken."<ref name=Karnow549>Karnow, p. 549.</ref> According to Clark Clifford, at the time of the initial attacks, the reaction of the U.S. military leadership "approached panic".<ref>Clifford, p. 474.</ref> Although Westmoreland's appraisal of the military situation was correct, he made himself look foolish by continuously maintaining his belief that Khe Sanh was the real objective of the communists and that 155 attacks by 84,000 troops was a diversion (a position he maintained until at least 12 February).<ref>Zaffiri, p. 283. Clifford, p. 476.</ref> ''Washington Post'' reporter Peter Braestrup summed up the feelings of his colleagues by asking "How could any effort against Saigon, especially downtown Saigon, be a diversion?"<ref>Braestrup, p. 108.</ref>

====Saigon====
Although Saigon was the focal point of the offensive, the communists did not seek a total takeover of the city.<ref>Andrew Wiest, ''The Vietnam War, 1956-1975''. London: Osprey Publishing, 2002, p. 41</ref> Rather, they had six primary targets to strike in the downtown area: the headquarters of the ARVN General Staff; the Independence Palace, the American Embassy, the Long Binh Naval Headquarters, and the National Radio Station. These objectives were all assaulted by small elements of the local C-10 Sapper Battalion. Elsewhere in the city or its outskirts, ten NLF Local Force Battalions attacked the central police station and the Artillery Command and the Armored Command headquarters (both at Go Vap). The plan called for all these initial forces to capture and hold their positions for 48 hours, by which time reinforcements were to have arrived to relieve them. 
thumb|left|250px|Attacks on Saigon
The defense of the Capital Military Zone was primarily a South Vietnamese responsibility and it was initially defended by eight ARVN infantry battalions and the local police force. By 3 February they had been reinforced by five ARVN Ranger Battalions, five Marine Corps, and five ARVN Airborne Battalions. U.S. Army units participating in the defense included the 716th Military Police Battalion, seven infantry battalions (one mechanized), and six artillery battalions.<ref>Stanton, p. 215. For a detailed description of U.S. participation in the defense see Keith W. Nolan, ''The Battle of Saigon, Tet 1968''. New York: Pocket Books, 1996.</ref> 

Faulty intelligence and poor local coordination hampered the communist attacks from the outset. At the Armored Command and Artillery Command headquarters on the northern edge of the city, for example, the communists planned to utilize captured tanks and artillery pieces to further support the offensive. To their dismay, they found that the tanks had been moved to another base two months earlier and that the breech blocks of the artillery pieces 
had been removed, rendering them useless.<ref>Westmoreland, p. 326.</ref> One of the most important Vietcong targets was the National Radio Station. Vietcong troops had brought along a tape recording of Hồ Chí Minh announcing the liberation of Saigon and calling for a "General Uprising" against the Thieu regime. The building was seized and held for six hours but the occupiers were unable to broadcast due to the cutting off of the audio lines from the main studio at the tower (which was situated at a different location) as soon as the station was seized. 
<!-- Unsourced image removed: thumb|left|200px|Dead Vietcong sappers in the chancery compound of the U.S. Embassy -->
The U.S. Embassy in Saigon, a massive six-floor building situated within a four acre compound, had only been completed in September. At 02:45 it was attacked by a 19-man sapper team that blew a hole in the eight-foot high surrounding wall and charged through. With their officer killed in the initial attack and their attempt to gain access to the building having failed, however, the sappers simply milled around in the chancery grounds until they were all eliminated by reinforcements. By 09:20 the embassy and its grounds were secured.

Throughout the city, small squads of NLF troops fanned out to attack various officers and enlisted men's billets, homes of ARVN officers, and district police stations. Provided with "blacklists" of military officers and civil servants, they began to round up and execute any that could be found. Brutality begat brutality. On 1 February General Nguyen Ngoc Loan, chief of the National Police Force, publicly executed an Vietcong officer captured in civilian clothing in front of a photographer and film cameraman. What was not explained in the wake of the distribution of the captured images was that the suspect had just taken part in the murder of one of Loan's most trusted officers and his entire family.<ref>The South Vietnamese Ambassador, Bui Diem, stated that such images "crystallized the war's brutality without providing a context within which to understand the events they depicted." Bui Diem, ''In the Jaws of History''. Bloomington IN: Indiana University Press, 1999. There was little mention in the American media of the hundreds of South Vietnamese executed in Saigon by the communists.</ref>

Outside the city proper, two NLF battalions attacked the U.S. logistical and headquarters complex at Long Binh. Bien Hoa Air Base was struck by a battalion, while the adjacent ARVN III Corps headquarters was the objective of another. Tan Son Nhut Air Base, in the northwestern part of the city, was attacked by three battalions. Fortunately for the allies, a combat-ready battalion of ARVN paratroopers, awaiting transport to Da Nang, went instead directly into action and halted the attack.<ref>Hoang, p. 40.</ref> A total of 35 communist battalions, many of whose troops were undercover cadres who had lived and worked within the capital or its environs for years, had been committed to the Saigon objectives.<ref>Willbanks, p. 32.</ref> By dawn, most of the attacks within the city center had been eliminated, but severe fighting between NLF and allied forces erupted in the Chinese suburb of Cholon around the Phu Tho racetrack, which was being utilized as an Vietcong staging area and command and control center. Bitter and destructive house-to-house fighting erupted in the area and, on 4 February, the residents were ordered to leave their homes and the area was declared a free fire zone. Fighting in the city came to a close only after a fierce battle between ARVN Rangers and Vietcong forces on 7 March.

Except at Hue and mopping-up operations in and around Saigon, the first surge of the offensive was over by the second week of February. The U.S. estimated that during the first phase (30 January - 8 April), approximately 45,000 communist soldiers were killed and an unknown number were wounded. For years this figure was held as excessive, but it was confirmed by Stanley Karnow in Hanoi in 1981.<ref>Don Oberdorfer, ''Tet!''. Baltimore: The Johns Hopkins University Press, 1971, p. 261, See also Palmer, p. 254 and Karnow, p. 534.</ref> Westmoreland claimed that during the same period 32,000 communist troops were killed and another 5,800 captured.<ref name=Westmoreland332/> The South Vietnamese suffered 2,788 killed, 8,299 wounded, and 587 missing in action. U.S. and other allied forces suffered 1,536 killed, 7,764 wounded, and 11 missing.<ref>Department of Defense, ''CACCF: Combat Area [Southeast Asia] Casualties Current File, as of Nov. 1993, Public Use Version''. Washington DC: National Archives, 1993.</ref>

====Huế====

thumb|right|200px|Hue and the Citadel
At 03:40 on the foggy morning of 31 January, allied defensive positions north of the Perfume River in the city of Hue were mortared and rocketed and then attacked by two battalions of the 6th PAVN Regiment. Their target were the ARVN 1st Division headquarters located in the Citadel, a three-square mile complex of palaces, parks, and residences that were surrounded by a moat and a massive earth and masonry fortress built in 1802. The undermanned ARVN defenders, led by General Ngo Quang Truong, managed to hold their position, but the majority of the Citadel fell to the communists. On the south bank of the river, the 4th North Vietnamese Regiment attempted to seize the local MACV headquarters, but was held at bay by a makeshift force of approximately 200 Americans. The rest of the city was overrun by communist forces which initialy totaled approximately 7,500 men.<ref>Palmer, p. 245. These units included the 12th Vietcong Battalion and the Hue City Vietcong Sapper Battalion.</ref> Both sides then rushed to reinforce and resupply their forces. Lasting 26 days, the battle of Huế became one of the longest and bloodiest single battles of the Vietnam War.

During the first days of the North Vietnamese occupation, allied intelligence vastly underestimated the number of communist troops and little appreciated the effort that was going to be necessary to evict them. General Westmoreland informed the Joint Chiefs that "the enemy has approximately three companies in the Hue Citadel and the marines have sent a battalion into the area to clear them out."<ref>Jack Schulimson, et al, ''1968''. Washington DC: History and Museums Division, United States Marine Corps, 1997, p. 175. For a detailed description of U.S. participation in the battle see Keith W. Nolan, ''Battle for Hue, Tet 1968''. Novato CA: Presidio Press, 1983.</ref> Since there were no U.S. formations stationed in Hue, relief forces had to move up from Phu Bai, eight kilometers to the southeast. In a misty drizzle, U.S. Marines of the 1st Marine Division and soldiers of the 1st ARVN Division and Marine Corps cleared the city street by street and house by house, a deadly and destructive form of urban combat that the U.S. military had not engaged in since the Battle of Seoul during the Korean War, and for which its men were not trained.<ref name=DouganWeiss28>Dougan & Weiss, p. 28.</ref> Due to the historical and cultural significance of the city, American forces did not immediately apply air and artillery strikes as widely as it had in other cities. 
thumb|left|300px|U.S. Marines advance past an [[M-48 tank during the battle for Hue]]
Outside Hue, elements of the U.S. 1st Air Cavalry Division and the 101st Airborne Division fought to seal communist access and cut off their lines of supply and reinforcement. By this point in the battle 16 to 18 communist battalions (8,000-11,000 men) were taking part in the fighting for the city itself or the approaches to the former imperial capital.<ref name=Schulimson213>Schulimson, p. 213.</ref> Two of the North Vietnamese regiments had made a forced march from the vicinity of Khe Sanh to Hue in order to participate. During most of February, the allies gradually fought their way towards the Citadel, which was only taken after four days of intense struggle. The city was not declared recaptured by U.S. and ARVN forces until 24 February, when members of the 2nd Battalion, 3rd Regiment, 1st ARVN Division raised the South Vietnamese flag over the Palace of Perfect Peace. 

L''''offensive du Têt''' est une campagne militaire menée par les forces combinées du Front national pour la libération du Viêt Nam (ou Viet Cong) et de l'Armée populaire vietnamienne pendant la guerre du Viêt Nam. 
Les buts poursuivis étaient le soulèvement de la population sud-vietnamienne contre la République du Viêt Nam, démontrer que les déclarations américaines selon lesquelles la situation s’améliorait étaient fausses, et dévier la pression militaire pesant sur les campagnes vers les villes sud-vietnamiennes.

L’offensive commence prématurément le 30 janvier Tet''. Le 31 janvier,  soldats communistes attaquèrent plus de 100 villes à travers le pays dans la plus grande opération militaire conduite à ce point de la guerre<ref name=DouganWeiss8>Dougan & Weiss, p. 8.</ref>.

Les attaques prennent les Alliés par surprise mais sont contenues et repoussées rapidement, le FNL se voit infliger d’énormes pertes. Bien que l’offensive soit un désastre militaire, elle choqua l’opinion américaine, tenue dans la croyance que les nord-vietnamiens étaient incapables d’un tel assaut, et affecte profondément l’administration de Lyndon Johnson dont de nombreuses personnalités se positionnent contre cette guerre, ce qui en altère décisivement le cours. 

thumb|right|300px|L'offensive de la [[Têt (Viêt-Nam)|fête du Têt Nguyên Dán constitue une très mauvaise surprise pour l'État-major américain ; les Viet-Cong attaquent simultanément les contingents de l'US Army dans leurs bases, dans leurs points de déploiement dans la République du Viêt Nam. <br /> Le front de diversion de Khe Sanh, antérieur à l'offensive, est indiqué par le trait rouge.]]

==Préparation==
===La situation aux Etats-Unis===

Pendant l'automne 1967, deux questions occupent les Américains: La guerre de position, dont le but est l'épuisement de l'adversaire, fonctionne-t-elle ? Qui est en train de gagner la guerre ? La CIA évalue le nombre d'homme du FLN à environ 430.000. Le renseignement du commandement militaire au Vietnam maintient de son côté que le nombre ne dépasse pas 300.000<ref name=DouganWeiss22>Dougan & Weiss, p. 22.</ref>. Les généraux sont inquiets de l'impact qu'aurait la révélation de chiffres trop élevés, qui montreraient que le FLN et l'armée nord-vietnamienne pourraient poursuivre la guerre de position<ref name=DouganWeiss22>Dougan & Weiss, p. 22.</ref>. Un compromis est trouvé qui exclue des chiffres les effectifs irréguliers.

Pendant la deuxième moitié de 1967, le gouvernement s'inquiète des critiques, qui viennent de l'intérieur comme de l'extérieur, et et des rapports indiquant une baisse du soutien populaire de sa politique vietnamienne. Selon des sondages, la part des citoyens estimant que les Américains auraient fait une erreur en envoyant les troupes au Vietnam était montée de 25% en 1965 à 45% en décembre 1967<ref name=DouganWeiss68>Dougan & Weiss, p. 68.</ref>. Cette tendance était alimentée non pas par un jugement moral sur la guerre, mais sur les pertes croissantes, les hausses d'impôts et le sentiment qu'aucune issue au conflit n'apparaissait<ref>Stanley Karnow, ''Vietnam''. New York: Viking, 1983, p. 545 & 546.</ref>. Un sondage du mois de novembre novembre indique que 55% réclament une politique plus dure, traduisant le sentiment que quelles que soit les raisons de la présence américaine au Vietnam, l'important est de remporter la victoire<ref name=Karnow546>Karnow, p. 546.</ref>. Le gouvernement lance une campagne pour dissiper la croyance que le conflit est bloqué et pour convaincre le public du succès de sa politique. Les médias sont inondés de nouvelles optimistes. Statistiques, déclarations officielles de généraux et politiques concourent à cette campagne.

Le général Westmoreland, s'adressant au ''National Press Club'' le 21 novembre, annoncent qu'en cette fin de 1967, les communistes sont incapables de monter une offensive majeure. A la fin de l'année, le taux d'approbation du gouvernement augmente de 8% mais début janvier, un sondage Gallup indique que 47% des Américains désapprouvent la conduite de la guerre par le Président Johnson.

===La préparation communiste===

Hanoi prépare une offensive pour l'hiver-printemps 1968 dès le début de 1967. On sait peu de chose sur la préparation de l'offensive "Offensive Générale, Soulèvement Général" en raison des réticences vietnamiennes à la révéler et des historiens militaires à la discuter, même des dizaines d'années après.<ref>David Elliot, ''The Vietnamese War'', Vol. 2, Armonk NY: M.E. Sharpe, 2003, p. 1055.</ref> Dans la littérature officielle du régime, la décision de lancer le Tet est souvent présentée comme le résultat de l'échec américain à remporter la guerre rapidement, l'échec des bombardements contre le Nord Vietnam, et le sentiment anti-guerre qui s'exprimait dans la population américaine<ref>Lien Hang T. Nguyen, ''The War Politburo'' in ''Journal of Vietnamese Studies''. Vol. 1, Numbers 1 & 2, p. 4.</ref>.

En réalité la décision signale la fin d'un désaccord d'une dizaine d'année au sein de la direction du parti. Les modérés estimaient que la viabilité économique du nord était prioritaire sur un effort de guerre conventionnelle et massive, il suivaient la ligne soviétique de coexistence pacifique, qui prônait la réunification par des moyens politiques. On trouve à la tête de cette faction le théoricien Trường Chinh et le ministre de la défense Võ Nguyên Giáp. Les militants, en revanche, avaient tendance à suivre la politique étrangère dessinée par la République populaire de Chine et appelaient à une réunification par des moyens militaires et rejetaient les négociations. Ce groupe était mené par les "frères Le" - le premier secrétaire du parti Lê Duẩn  et Lê Đức Thọ. A partir du milieu des années 60, les militants dictent la conduite dans la guerre au sud Vietnam<ref>Nguyen, pgs. 15 & 16.</ref>.
 
Le général Nguyen Chi Thanh, qui dirige l'effort militaire dans le sud du Vietnam, commissaire politique et commandant en chef faisait partie du camp des militants. Sous son commandement, qui étrangement n'imitait pas la forme de guérilla utilisée par Mao, les nord-vietnamiens avient suivi étape par étape l'escalade militaire du conflit<ref name=Nguyen20>Nguyen, p. 20. See also Wirtz, pgs. 30-50.</ref>.

En 1966-1967, après que les alliés ont infligé des pertes massives et détruit l'économie nord-Vietnamienne, les modérés appellent à une révision de la stratégie vers d'avantage de guérilla et soutiennent que les Américains ne peuvent être défaits par une guerre conventionnelle. Ils prêchent la conduction simultanée de combats et de négociations. En 1967 les choses se dégradent au point que Le Duan ordonne à Thanh d'accroitre la part de guérilla<ref name=Nguyen22>Nguyen, p. 22.</ref> .

Une troisième tendance émerge alors, dirigée par le chef du parti, Hô Chi Minh, Lê Đức Thọ, et le ministre des affaires étrangères Nguyen Duy Trinh, qui appelle à des négociations<ref>Contrairement à la croyance occidentale, Ho Chi Minh avait été écarté politiquement depuis 1963 et prenait peu part aux décisions quotidiennes du Politburo ou du Secrétariat. Nguyen, p. 30.</ref>. Pendant les premiers mois de 1967 la stratégie militaire est débattue par radio entre Thanh et son rival pour la direction militaire, Giap<ref>Wirtz, pgs. 36-40 & 47-49.</ref>. Ce dernier<ref>Hoang, pgs. 15 & 16. See also Doyle, Lipsman, & Maitland, p. 56.</ref> prône la guérilla contrairement à Thanh<ref name=Hoang16>Hoang, p. 16.</ref>.

Ces négociations ont d'importantes implications sur la poursuite des livraisons d'équipements, envers lesquelles le nord-Vietnam est totalement dépendant. Pékin prône le modèle militaire utilisé par Mao, sorte de guerre mobile et de guérilla, la Chine souhaite éviter d'être entrainée dans le conflit comme lors de la guerre de Corée. Elle repousse l'idée de négociations quand Moscou les prône de même que la conduite d'une guerre conventionnelle. La position Nord-Vietnamienne consiste dès lors à maintenir un équilibre<ref>Nguyen, pgs. 18-20.</ref>.

Le 27 juillet 1967, des centaines de pro-soviétiques, modérés du parti, officiers et administrateurs sont arrêtés pour affirmer l'indépendance du pays contre ses alliés étrangers dans ce qui est parfois appelée l'affaire des révisionnistes anti-parti<ref name=Nguyen24>Nguyen, p. 24.</ref>. L'explication de ces arrestations est que le politburo a décidé en faveur d'une offensive générale<ref name=Nguyen27>Nguyen, p. 27.</ref>. La position des militants triomphe : rejet des négociations, abandon de la guérilla, soulèvement général dans les villes du sud Vietnam.

Le plan "Offensive Générale, Soulèvement Général" est ébauché dans les quartiers de Thanh en mai 1967. Le 6 juillet, après avoir fait accepter son plan par le Politburo, Thanh meurt d'un arrêt cardiaque après avoir trop bu<ref>''Victory in Vietnam'', p. 380. Pendant des années les historiens occidentaux ont cru que Thanh était mort de blessures reçues pendant un raid aérien. Nguyen, fn. 147 </ref>.

Les militants estiment que la popularité du gouvernement sud-vietnamien et des Américains est très faible et que la population se soulèverait en leur faveur lors de l'offensive, ce qui permettrait une victoire rapide. Ils tenaient pour acquise l'inefficacité de l'armée du sud. Déclencher l'offensive permettait d'en finir avec les appels aux négociations des colombes, les critiques de la stratégie militaire, les diatribes chinoises sur la perfidie soviétique et les pressions soviétiques à négocier<ref name=Nguyen24>Nguyen, p. 24.</ref>.

La décision de déclencher l'offensive lors du Tet est prise en octobre. Depuis le début du conflit, le Têt « Nguyên Đán », ou célébration du nouvel an, qui se situait entre le 20 janvier et le 19 février, marquait une période de trêve dans les combats. C’était pourquoi, en juillet 1967, les dirigeants du Front national pour la libération du Viêt Nam FNL et de la République démocratique du Viêt Nam décidaient de lancer une attaque surprise à ce moment-là. Contrairement à une croyance répandue, Giap n'est pas l'auteur du plan. Le général l'a seulement revu<ref>Nguyen, p. 34. William J. Duiker, ''Communist Road to Power''. Boulder CO: Westview Press, 1996, p. 288. Voir aussi Doyle, Lipsman, & Maitland, p. 56.</ref>, probablement en taisant ses critiques pour ne pas être victime de la purge des militants. De toute façon, l'échec éventuel serait blamé sur les militants.

L'opération se diviserait en deux phases : attaques aux frontières pour divertir les forces américaines des véritables objectifs : attaques simultanées sur les bases américaines et les villes du sud Vietnam, en particulier Hue et Saïgon. Une attaque sur Khe Sanh au même moment éloignerait les forces militaires nord-vietnamiennes mais Giap l'estime nécessaire pour assurer le ravitaillement et divertir les Américains<ref name=Duiker299>Duiker, p. 299.</ref>. L'offensive vise à convaincre l'opinion sud-vietnamienne, pas américaine, et l'inciter à se soulever <ref name=Hoang26>Hoang, p. 26.</ref>.

Selon le général Tran Van Tra, qui remplace Thanh, l'offensive se divise en trois phases : une première à partir du 31 janvier, assaut dans tous le pays principalement par les forces du FNL. En même temps : propagande active pour inciter aux soulèvements et désertions. Le but est d'obtenir une victoire complète ou la formation d'un gouvernement de coalition ainsi que le retrait américain. En cas d'échec, d'autres opérations affaibliraient l'ennemi de façon à obtenir un règlement négocié<ref>Tran Van Tra, ''Tet'', p. 40. </ref>. La phase 2 est prévue à partir du 5 mai, et la phase 3 à compter du 17 août.

En janvier 1968, 81.000 tonnes de matériel et 200.000 troupes ont déjà fait le voyage vers le Vietnam sud à travers la piste Hô Chi Minh<ref>''Victory in Vietnam,'', p. 208. See also Doyle, Lipsman, & Maitland, ''The North'', p. 46.</ref>. Pour parfaire son opération, Hanoi déclenche une offensive diplomatique à la fin de 1967, appelant à l'arrêt unilatéral des bombardements sur le Vietnam nord, l'opération Rolling Thunder<ref name=DouganWeiss10>Dougan & Weiss, p. 10.</ref>.

Le renseignement sud-vietnamien, et américain estiment les forces communistes au sud-vietnam en janvier 1969 à 323.000 hommes dont 160.000 du FLN, 130.000 réguliers de l'armée du nord et 33.000 personnes consacrées à la logistique<ref name=Hoang10>Hoang, p. 10.</ref>.

===L'impréparation des Alliés===

Des signes de préparation militaire sont relevés par les Alliés. Pendant l'été et l'automne 1967, les deux services de renseignements américain et sud-vietnamien relèvent une importante modification du planning militaire du FLN et de l'armée nord-vietnamienne. A la mi-décembre, les Alliés sont convaincus que quelque chose de gros se prépare. Le nombre de camion dénombrés descendant vers le sud à travers la piste Ho Chi Minh grimpe de 480 par mois à 1116 en octobre. En novembre, on en compte 3823 et en décembre 6315<ref>Steven Hayward, ''The Tet Offensive: Dialogues'', April 2004. http://www.ashbrook.org/publicat/dialogue/hayward-tet.html#2r</ref>. Le 20 décembre, le général William Westmoreland alerte Washington de l'acroissement prévisible de l'effort communiste dans tout le pays pour une période de temps restreinte<ref name=DouganWeiss11>Dougan & Weiss, p. 11.</ref> .

Malgré ces indications, les Alliés furent surpris par l'ampleur de l'attaque. <!---placer HK--->D'une perspective américaine, un assaut pareil n'était pas crédible.

Du printemps à la fin de 1967, le commandement américain assistait perplexe à diverses actions nord-vietnamiennes et viet congs sur les territoires frontaliers. Khe Sanh est attaquée prématurément. La plus importante de ces batailles se déroule autour de Dak To en octobre et novembre, entre 1200 et 1600 Nord-Vietnamiens et 262 soldats américains perdent la vie. Le renseignement ne réussit pas à déterminer l'objectif des Nord-Vietnamiens, déclenchant de larges actions dans des régions reculées où l'armée américaine peut riposter sans contrainte. Tactiquement et stratégiquement, ces opérations semblent n'avoir aucun sens<ref>Dougan & Weiss, p. 11. L'Offensive du Tet serait plus tard utilisée dans un livre de West Point pour illustrer un échec du renseignement de l'ampleur de Pearl Harbor en 1941 ou l'offensive des Ardennes en 1944." Lieutenant Colonel Dave R. Palmer: ''Current Readings in Military History''. Clifford, p. 460.
</ref>. En fait, les communistes ont réussi à fixer l'attention du commandement américain sur les frontières et a écarter le bouclier américain protégeant les zones les plus peuplées de la côte et des villes<ref>Terrence Maitland & Peter McInerney, ''A Contagion of War''. Boston: Boston Publishing Company, 1983, pgs. 160-183.</ref> .

Westmoreland s'inquiète pour la situation à Khe Sanh, où, le 21 janvier 1968, une force estimée de 20 à 40.000 Nord-Vietnamiens assiège la garnison américaine. Le commandement est convaincu que l'ennemi cherche à prendre la base avant de s'emparer des provinces les plus au nord, au moyen d'un effort militaire considérable<ref>Dave R. Palmer, ''Summons of the Trumpet''. New York: Ballentine, 1978, pgs. 229 & 233.</ref>. Il déploie en conséquence 250.000 hommes.

Cette évolution pose des questions.  Le lieutenant général Frederick C. Weyand, commandant de forces américaines dans le Corps II. Weyand, ancien officier du renseignement, se méfie des activités qui se déroulent dans son secteur et notifie ses préoccupations à Westmoreland le 10 janvier 1968. Westmoreland ordonne alors à 15 bataillons de se redéployer depuis des positions près de la frontière cambodgienne vers les faubourgs de Saïgon<ref name=DouganWeiss8>Dougan & Weiss, p. 8.</ref>. Ce redéploiement eut des conséquences décisives<ref name=Palmer235>Palmer, p. 235.</ref>.

Au début de janvier 1968, les Américains ont déployé 331.098 soldats et 78.013 marines, soit neuf divisions, un regiment de blindés et deux brigades au Sud-Vietnam. Des forces australiennes, thailandaises et coréennes les rejoignent<ref name=Stanton195>Shelby L. Stanton, ''Rise and Fall of an American Army''. New York: Dell, 1985, p. 195.</ref>. Les forces sud-vietnamiennes sont au nombre de 350.000 réguliers<ref name=DouganWeiss124>Dougan & Weiss, p. 124.</ref>. Elles sont soutenues par 151.000 hommes de forces régionales et 149.000 hommes de milices locales<ref name=Willbanks7>James H. Willbanks, ''The Tet Offensive'' New Haven CT: Yale University Press, 2006, p. 7.</ref>.

Dans les jours précédant l'offensive, les alliés se relâchent. Le Nord Vietnam annonce une trêve pour le Tet, soit du 27 janvier au 3 février 1968.

Le 8 janvier, des cadres du FLN sont arrêtés avec des cassettes appelant au soulèvement de la population dans les villes "déjà occupées de Saigon, Hue, and Da Nang"<ref name=Hoang35>Hoang, p. 35.</ref>. Des troupes sont mises en alerte mais les Alliés ne s'en inquiètent guère plus. Le 30 janvier, deux cents officiers supérieurs assistent à une fête sans se douter de rien<ref name=Zaffiri280>Samuel Zaffiri, ''Westmoreland''. New York,: William Morrow, 1994, p. 280.</ref>.

Si Westmoreland a eu des craintes, il les a mal communiquées. Même s'il alerte Washington entre le 25 et le 30 janvier au sujet de préparations de larges attaques communistes, personne, ni à Washington<ref name=Hammond342>Hammond, p. 342.</ref><ref name=Zaffiri280>s Zaffiri, p. 280.</ref> ni à Saïgon ne s'attend à ce qui va arriver.

==Une offensive surprise==

Que ce soit par accident ou volontaire, la première vague d’attaques commence peu après minuit le 30 janvier quand les cinq capitales provinciales dans Corps II et Da Nang, dans Corps I, sont attaquées. Nha Trang, un des quartiers généraux des forces américaines, est la première touchée, suivie peu après de Ban Me Thuot, Kontum, Hôi An, Tuy Hoa, Da Nang, Qui Nhon, et Pleiku. Durant toutes ces operations, les communistes suivent une même méthode : attaques au mortier ou roquettes suivies rapidement de massifs assauts terrestres conduits par des forces du FLN de l’ampleur d’un bataillon (parfois soutenu par l’armée nord-vietnamienne). Ces forces joignent ensuite des cadres locaux du FLN qui les guident vers les quartiers généraux les plus important et la station de radio. Les opérations cependant n’étaient pas bien coordonnées au niveau local et, au lever du jour, presque toutes les forces communistes avaient été éloignées de leur objectif. Le général Phillip B. Davidson, nouveau chef du renseignement des forces militaires américaines notifie Westmoreland que “ceci s’apprête à arriver dans le reste du pays ce soir et demain matin” <ref>William C. Westmoreland, ''A Soldier Reports''. New York: Doubleday, 1976, p. 323. Traduction libre de "This is going to happen in the rest of the country tonight and tomorrow morning".</ref>. Toutes les forces américaines sont placées en état d’alerte maximum, des demandes en ce sens sont adressés aux forces de l’ARVN. Les principaux intéressés, cependant, n'en saisissent pas l'urgence: les ordres annulant les départs à l’occasion de la trêve arrivent trop tard ou sont ignorés.

thumb|right|250px|Trappe d'accès au [[Tunnel de Củ Chi|réseau de tunnels de Củ Chi qui servit aux assaillants à s'infiltrer profondément dans le pays tenu par l'ennemi sans se faire repérer.]]

thumb|left|250px|Des marines combattent dans le village de Hamo
A 03:00 du matin le Quảng Ngãi ainsi que des bases U.S. bases à Phu Bai et Chu Lai dans Corps I; Phan Thiết, Tuy Hoa, et des installations U.S. à Bong Son et An Khe dans Corps II; et Cần Thơ et Vĩnh Long dans Corps IV. Le jour suivant; Bien Hoa, Long Thanh, Bình Dương dans Corps III et Kien Hoa, Dinh Tuong, Go Cong, Kiên Giang, Vinh Binh, Ben Tre, et Kien Tuong dans Corps IV sont assaillis. La dernière attaque de l’opération initiale est lancée contre Bac Lieu dans Corps IV le 10 février. Un total d’approximativement 84.000 troupes communistes participe aux attaques pendant que des milliers les assistent comme renfort ou pour bloquer. <ref>Westmoreland, p. 328. Palmer donne un nombre de 70.000, p. 238.</ref> Les forces communistes tirent au mortier ou à la roquette sur tous les aéroports majeurs alliés et attaquent 64 districts de la capitale et une grande quantité de villages.

Dans la majorité des cas la défense contre l’offensive générale a été gérée par les autorités sudvietnamienne. Des milices locales ou des forces de l’ARVN, soutenues par la police nationale, rejetaient en général les assaillants en deux ou trois jours, parfois en quelques heures ; mais des combats lourds se poursuivirent plusieurs jours à Kontum, Ban Me Thuot, Phan Thiet, Can Tho, et Ben Tre.<ref>Westmoreland, p. 328.</ref> L’issue était généralement déterminée par la compétence des commandants locaux – certains étaient impressionnants, d’autres lâches ou incompétents. Pendant cette crise cruciale,aucune unité sud-vietnamienne ne fait défection pour les Communistes.<ref name=Westmoreland332>Westmoreland, p. 332.</ref>

Le général Westmoreland, bien qu’il affirme avoir réagi avec optimisme aux attaques, apparait à son entourage abasourdi et profondément choqué. <ref name=Karnow549>Karnow, p. 549.</ref> Selon Clark Clifford, au moment des attaques initiales, la réaction du commandement militaire américain tend vers la panique.<ref>Clifford, p. 474.</ref> Westmoreland maintient jusqu’au 12 février que Khe Sanh est le véritable objectif des communistes, que 155 attaques par 84.000 troupes est une diversion, apparaissant démentiel.<ref>Zaffiri, p. 283. Clifford, p. 476.</ref>

===Saigon===
Bien que Saïgon soit le point central de l’offensive, les communistes ne recherchent pas une conquête complète.<ref>Andrew Wiest, ''The Vietnam War, 1956-1975''. London: Osprey Publishing, 2002, p. 41</ref> Ils ont des cibles principales : les quartiers généraux du commandement de l’ARVN, le Palais de l’Indépendance, l’ambassade américaine, the Long Binh Naval Headquarters, et la station de radio nationale. Le plan requiert de ces forces initiales qu’elles tiennent leur position 48h avant d'être relevées.
 
Un renseignement de mauvaise qualité et une coordination locale très faible compromet les attaques communistes dès leur déclenchement. Les communistes avaient prévu par exemple d’utiliser les chars et les pièces d’artillerie qui devaient se trouver dans certains quartiers généraux de l’armée mais les chars avaient été déplacés deux mois avant et les pièces d’artillerie étaient hors d'état. <ref>Westmoreland, p. 326.</ref> Une des cibles les plus importantes était la station de radio nationale. Les troupes du FLN avaient amené un enregistrement de Hồ Chí Minh annonçant la liberation de Saïgon et appelant à un soulèvement général contre le régime de Thieu. Le bâtiment fut pris et tenu pendant six heures mais ses occupants furent incapables de diffuser, les lignes ayant été coupées depuis un studio situé en un autre endroit dès que la station avait été prise.

L’ambassade américaine à Saïgon, un bâtiment massif de six étages situé dans un large complexe, venait d’être terminé en septembre. A 02:45 elle est attaquée par une équipe de sapeurs de 19 hommes qui fait exploser un trou dans l’enceinte puis charge. Leur officier ayant été tué dans l’attaque initiale et leur tentative d’accéder au bâtiment ayant échoué, les sapeurs errent autour de l’ambassade jusqu’à ce que des renforts les éliminent. A 09:20 l’ambassade et ses environs sont sécurisés.

A travers la ville, de petits groupes du FLN s’éparpillent pour attaquer les officiers, les casernes de conscrits, les maisons des officiers de l’ARVN et les stations de police des districts. Dotés de “listes noires” d’officiers militaires et de fonctionnaires, ils exécutent tous ceux qu’ils trouvent. La brutalité engendra la brutalité, le 1er février, le général Nguyễn Ngọc Loan, chef de la force de police nationale, exécute publiquement un officier du FLN capturé en habits civils devant un photographe et un caméraman. Ce qui n’était pas expliqué quand l’image fut distribuée était que le suspect venait de prendre part au meurtre d’un des officiers de confiance de Loan, ainsi que de toute sa famille.

thumb|right|200px|L’infamante photo du général Nguyen Ngoc Loan exécutant un officier du FLN à Saïgon, prise par Eddie Adams
Un total de 35 bataillons de communistes, dont la plupart travaillait et vivait dans la ville depuis des années, avait été affecté aux objectifs dans Saïgon.<ref>Willbanks, p. 32.</ref> A l’aube, le clair des attaques dans le centre-ville était éliminé mais de sévères combats entre FLN et forces alliées avaient lieu dans les faubourgs chinois de Cholon près de la route Phu Tho, utilisé comme centre de commandement par le FLN. Un combat de rue, maison par maison, se déroule le 4 février, les habitants de Cholon reçoivent l'ordre de quitter leur maison et la zone est déclarée free fire zone. La bataille se termine le 7 mars grâce au renfort de troupes d'élites sud-vietnamienne.

Mis à part Hue et les opérations de nettoyage dans Saïgon et ses alentours, la première vague de l’offensive est terminée dès la seconde semaine de février. Les Américains estiment que durant la première phase (30 janvier - 8 avril), approximativement 45.000 FLN et soldats PAVN son tués, et un nombre inconnu blessé. Pendant des années, cette estimation fut tenue pour excessive, mais elle fut confirmée par Stanley Karnow à Hanoi en 1981.<ref>Don Oberdorfer, ''Tet!''. Baltimore: The Johns Hopkins University Press, 1971, p. 261, Voir aussi Palmer, p. 254 et Karnow, p. 534.</ref> Westmoreland affirme que durant la même période 32.000 communistes étaient tués et 5.800 capturés.<ref name=Westmoreland332/> Durant la même période les sud Vietnamiens subissent 2.788 tués, 8.299 blessés et 587 disparus. Les Etats-Unis et leurs autres allies subissent 1.536 tués, 7.764 blessés, et 11 disparus.<ref>Department of Defense, ''CACCF: Combat Area [Southeast Asia] Casualties Current File, as of Nov. 1993, Public Use Version''. Washington DC: National Archives, 1993.</ref>

===Huế===
A 03:40 dans le matin brumeux du 31 janvier, des positions alliées sont attaquées à Hue. Les défenseurs ARVN parviennent à maintenir leurs positions, dirigés par le général Ngo Quang Truong, mais la majorité de la citadelle tombe dans les mains communistes. La bataille sera sanglante et durera 28 jours.

Les alliés estiment que les forces nord-vietnmiennes ont entre 2500 et 5000 tués et 89 capturés dans la ville et alentours.<ref>Schulimson, p. 213. Un document communiste ultérieur par le AVRN indique que 1.042 soldats ont été tués dans la ville elle-même et que plusieurs fois ce nombre a été blessée. Hoang, p. 84.</ref> 216 U.S. Marines et soldats sont tués pendant les combats et 1609 blessés. 421 soldats de l’ARVN sont tués et 2.123 blessés, et 31 disparus. <ref name=Schulimson213>Schulimson, p. 213.</ref> Plus de 5.800 civils perdent la vie, 116.000 sont sans toit sur une population initiale de 140.000.<ref name=Schulimson216>Schulimson, p. 216.</ref> 

Après la reprise de la ville, on découvre des fosses communes contenant au total environ 2.800 personnes. La cause de des exécutions demeure controversée.

===Khe Sanh===

L’attaque sur Khe Sanh, qui commence le 21 janvier, peut dans l’absolu avoir servi deux desseins – la tentative de prendre réellement la position ou attirer l’attention et les forces américaines loin des concentrations de population. Dans l’optique du general Westmoreland, la raison d’être de cette base était de provoquer les Nord-Vietnamiens dans une confrontation ciblée et prolongée sur une aire géographique restreinte qui permettrait l’utilisation d’une artillerie et de bombardements aériens massifs et infligerait de lourdes pertes dans une region relativement peu peuplée.<ref>Westmoreland, pgs. 339 & 340.</ref> A la fin de 1967, le MACV avait déplacé près de la moitié de ses bataillons de maneuvre à Corps I en anticipation d’une pareille bataille.

thumb|right|250px|Province nord de Quang Tri
Westmoreland (et les media américains, qui couvraient extensivement l’action) fit fréquemment d’inévitables comparaisons entre les actions à Khe Sanh et la bataille de Ðiện Biên Phủ, où une base française avait été assiégée puis conquise par les forces du Việt Minh commandées par le général Giap durant la première guerre d’Indochine.<ref>Westmoreland, p. 311.</ref> Westmoreland, qui connaissait le penchant de Nguyen Chi Thanh pour les opérations de grande envergure (mais pas son décès) croyait qu’il tenterait de réitérer sa victoire. Il se proposait de mettre en scène son propre "Dien Bien Phu à l’envers."<ref>Robert Pisor, ''The End of the Line''. New York: Ballentine, 1982, p. 61.</ref>  

Khe Sanh et ses 6.000 défenseurs, ARVN, U.S. Marines et armée américaine confondus, sont cernés par deux ou trois divisions de PAVN, totalisant approximativement 20.000 hommes. La bataille tourne largement au duel d’artilleries. Les avions américains conduisent des bombardements massifs par leurs B-52s. Un pont aérien ravitaille les troupes.