Editing Tet Offensive (section)

== U.S. unpreparedness ==
=== Suspicions and diversions ===
Signs of impending communist action were noticed 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 North Vietnamese 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>Hayward, ''[http://www.ashbrook.org/publicat/dialogue/hayward-tet.html#2r The Tet Offensive: Dialogues]''.</ref> On 20 December, Westmoreland cabled Washington that he expected the PAVN/VC "to undertake an intensified countrywide effort, perhaps a maximum effort, over a relatively short period of time."<ref name="DouganWeiss" />{{rp|11}}
[[File:Lieutenant General Frederick Weyand.jpg|thumbnail|right|upright|[[Lieutenant General]] [[Frederick Weyand]], commander of [[II Field Force, Vietnam (United States)|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 enemy's probable course of action based upon their capabilities, not their intentions. Since, in the allied estimation, the communists 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 name="HoangLung" />{{rp|39}} 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 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 name="DouganWeiss" />{{rp|11}} The Tet offensive would later be used 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''.<ref name=Clifford />{{rp|460}}

From early to late 1967, the U.S. command in Saigon was perplexed by a series of actions initiated by the PAVN/VC in the border regions. On 24 April a [[U.S. Marine Corps]] patrol prematurely triggered a [[The Hill Fights|PAVN offensive]] aimed at taking Khe Sanh Combat Base, the western anchor of the Marines' defensive positions in [[Quảng Trị Province]].<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 PAVN began shelling the U.S. Marine outpost of [[Con Thien]], just south of the [[Vietnamese Demilitarized Zone|Demilitarized Zone]] (DMZ).<ref name=Willbanks>Willbanks</ref>{{rp|16}} 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 DMZ.<ref>Morocco, pp. 174–176.</ref>

On 27 October, an ARVN battalion at [[Sông Bé province|Sông Bé]], the capital of [[Phước Long Province]], came under attack by an entire PAVN regiment. Two days later, another PAVN regiment attacked a U.S. Special Forces border outpost at [[Lộc Ninh, Bình Phước|Lộc Ninh]], in [[Bình Long Province]].<ref name=Willbanks/>{{rp|36}} This attack sparked a [[First Battle of Loc Ninh|ten-day battle]] that drew in elements of the [[1st Infantry Division (United States)|U.S. 1st Infantry Division]] and the ARVN [[18th Division (South Vietnam)|18th Division]] and left 800 PAVN troops dead at its conclusion.<ref name="HoangLung" />{{rp|9}}

The most severe of what came to be known as "the Border Battles" erupted during October and November around [[Battle of Dak To|Dak To]], another border outpost in [[Kon Tum Province]]. The clashes there between the four regiments of the PAVN [[1st Division (Vietnam)|1st Division]], the U.S. [[4th Infantry Division (United States)|4th Infantry Division]], the [[173rd Airborne Brigade Combat Team|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 PAVN and 262 U.S. troops had been killed.<ref name="HoangLung" />{{rp|9}}<ref name=Willbanks />{{rp|17}} MACV intelligence was confused by the possible motives of the North Vietnamese in prompting such large-scale actions in remote regions where U.S. artillery and aerial firepower could be applied indiscriminately, which meant that tactically and strategically, these operations made no sense. What the North Vietnamese 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>Maitland and McInerney,  pp. 160–183.</ref>

Westmoreland was more concerned with the situation at Khe Sanh, where, on 21 January 1968, a force estimated at 20,000–40,000 PAVN troops had besieged the U.S. Marine garrison. MACV was convinced that the PAVN 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 name="Palmer, pp. 229–233">Palmer, pp. 229–233.</ref> To deter any such possibility, he deployed 250,000 men, including half of MACV's U.S. maneuver battalions, to I Corps.

This course of events disturbed Lieutenant General [[Frederick Weyand]], commander of U.S. forces in III Corps, which included the sensitive [[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="DouganWeiss" />{{rp|8}} 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 offensive ===
[[File:South Vietnam Map.jpg|thumb|upright=1.2|South Vietnam, Corps Tactical Zones]]

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 Army]] infantry divisions, and the [[Republic of Korea Marine Corps]] brigade.<ref name="Stanton195">Stanton, p. 195.</ref> South Vietnamese strength totaled 350,000 regulars in the Army, [[Republic of Vietnam Air Force|Air Force]], [[Republic of Vietnam Navy|Navy]] and [[Republic of Vietnam Marine Corps|Marine Corps]].<ref name="DouganWeiss" />{{rp|124}} They were in turn supported by the 151,000-man [[South Vietnamese Regional Force]]s and 149,000-man [[South Vietnamese Popular Force]]s, which were the equivalent of regional and local militias.<ref name=Willbanks />{{rp|7}}

In the days immediately preceding the offensive, the preparedness of allied forces was relatively relaxed. Hanoi had announced in October that it would observe a seven-day truce from 27 January to 3 February for the Tet holiday, and the South Vietnamese military made plans to allow recreational leave for approximately half of its forces. General Westmoreland, who had already cancelled the truce in I Corps, requested that South Vietnam cancel the upcoming cease-fire, but President Thiệu (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="DouganWeiss" />{{rp|12}}

On 28 January, eleven VC cadres were captured in the city of [[Qui Nhơn]] while in possession of two pre-recorded audio tapes whose message appealed to the populace in "already occupied Saigon, Huế, and [[Da Nang]]".<ref name="HoangLung" />{{rp|35}} The following afternoon, General [[Cao Văn Viên]], chief of the South Vietnamese Joint General Staff,<ref>Sheehan, p. 778.</ref> 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, pp. 467–468.</ref> On the evening of 30 January, 200 U.S. officers—all of whom served on the MACV intelligence staff—attended a pool party at their 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&nbsp;... Of the 200-odd officers present, not one I talked to knew Tet was coming, without exception."<ref name="Zaffiri280">Zaffiri, p. 280.</ref>

Westmoreland also failed to communicate his concerns adequately to Washington. Although he had warned the President between 25 and 30 January that "widespread" communist 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.; Zaffiri, p. 280.<br />For a treatment of official statements predicting the offensive, see Peter Braestrup. ''Big Story'', New Haven, Connecticut: Yale University Press, 1983, 1:60–77.</ref> No one—in either Washington or Vietnam—was expecting what happened.

Weyand invited [[CBS News]] Correspondent [[John Laurence]] and [[Washington Post]] reporter [[Don Oberdorfer]] to his III Corps headquarters in the week before the Tet offensive to alert them that a major enemy attack was coming "just before or just after Tet." He said the Vietnamese had too much respect for the holiday to attack during Tet itself. Weyand said he had moved 30 U.S. and South Vietnamese battalions closer to Saigon to defend the city.<ref>Laurence, John (2002), The Cat from Hue: a Vietnam War Story, PublicAffairs Press.</ref><ref>Oberdorfer, Don (1971) Tet!: The Turning Point in the Vietnam War. Baltimore: The Johns Hopkins University Press. {{ISBN|0-8018-6703-7}}.</ref>