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Khe Sanh, Siege of

Khe Sanh, Siege of (1968).Among key engagements of the Vietnam War, the siege of Khe Sanh also marked one of the largest setpiece battles of that conflict. The relationship between Khe Sanh and the Tet Offensive of 1968 continues to be the most controversial aspect of the siege. In fighting prior to the offensive, U.S. commander Gen. William C. Westmoreland became convinced that this base at the northwestern corner of South Vietnam would be the major objective for North Vietnamese forces in the attack he expected. Instead, the forces directed by Gen. V. Nguyen Giap struck cities and towns throughout South Vietnam. Whether or not Hanoi mounted a deliberate deception remains at issue. In any case, Westmoreland's focus on Khe Sanh helped Hanoi gain position for its assaults at Tet.

In the prelude to the Khe Sanh siege, increasing numbers of Hanoi's troops were detected in the vicinity of the combat base, which had been a military post or Special Forces camp since July 1962. That Special Forces camp was first hit by mortar bombardment in January 1966; in May 1967, after the facility moved to nearby Lang Vei, it received a ground attack. U.S. Marines began operating in the area, establishing and improving the Khe Sanh combat base and gradually reinforcing it as the suspected North Vietnamese presence grew to an estimated 25,000–40,000 men. By January 1968, the combat base was manned by 6,806 American troops (including 5,905 Marines) under Col. David E. Lownds. There were also about 360 Americans and indigenous soldiers at Lang Vei Special Forces camp and another 175 troops in and around Khe Sanh village.

The events of the seventy‐eight day siege began with an attack on an outlying position (Hill 861) on 20/21 January 1968, coupled with a bombardment of the main base that destroyed much of the Marines' reserve ammunition. The force at Khe Sanh village withstood an attack the next night but was then withdrawn. There were several pitched battles for outposts but no more than probes at the combat base. These included the battles at Hill 861A (5 February), Lang Vei (7 February), and Hill 64 (8 February). All the posts except Lang Vei were successfully defended. On 21 February, there was a probe against South Vietnamese Ranger positions in the main base. The base and its outposts were heavily supported throughout the siege by U.S. airpower and artillery fire in an exceptional effort that General Westmoreland called Operation Niagara. It remains unclear whether the lack of a big North Vietnamese attack was intentional or resulted from losses inflicted by this firepower. Khe Sanh was relieved by an overland attack, Operation Pegasus, involving some 30,000 troops, that made contact with the isolated base on 7 April 1968. After a period of mobile action, the United States withdrew from Khe Sanh on 6 July.

Official U.S. figures for casualties, which exclude several sources of losses, amount to 205 killed and 816 wounded who were evacuated; a more detailed assessment indicates about 730 battle deaths, 2,598 wounded, and 7 missing. Losses during the period of mobile operations in the surrounding zone include another 326 killed, 1,888 wounded, and 3 missing. North Vietnamese losses have been estimated by Americans at between 10,000 and 15,000 in dead alone.
[See also Vietnam War: Military and Diplomatic Course.]


Robert Pisor , The End of the Line: The Siege of Khe Sanh, 1982.
Eric Hammel , Khe Sanh: Siege in the Clouds, an Oral History, 1989.
John Prados and and Ray W. Stubbe , Valley of Decision: The Siege of Khe Sanh, 1991.

John Prados

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