On 21 January 1968, two to three divisions of the People’s Army of Vietnam (PAVN) attacked the US Marine Combat Base at Khe Sanh in the northwest of Quảng Trị Province in the north of South Vietnam.
After increasing reports of PAVN forces occupying the area of Khe Sanh, American troops were sent to Khe Sanh to fortify the combat base and prevent it from being encircled and cut off. However, once the base came under siege, it was clear that it was surrounded. During this time, the base and hilltop outposts surrounding it were subjected to constant PAVN artillery, mortar and rocket attacks, and several infantry assaults. To support the Marine base, a massive aerial bombardment campaign was launched by the US Air Force. Over 100,000 tons of bombs were dropped by US aircraft and over 158,000 artillery rounds were fired in defence of the base. In the initial artillery bombardment, PAVN forces hit the base’s main store of ammunition and destroyed 90 per cent of its artillery and mortar rounds.
Despite American air support, as the Battle of Khe Sanh dragged on, PAVN troops gained the upper hand as the Tết Offensive took effect on 31 January 1968. As approximately 70,000 PAVN, National Liberation Front (NLF) and People’s Liberation Armed Forces of Vietnam (PLAF) troops launched coordinated attacks throughout South Vietnam, Khe Sanh became a huge distraction for American and Army of the Republic of Vietnam (ARVN) forces. Very quickly, due to the similarity with General Võ Nguyên Giáp’s diverting tactics against French forces in 1954, the Battle of Khe Sanh became synonymous with the Battle of Điện Biên Phủ.
In March, US Marines successfully broke through PAVN military lines in support for Khe Sanh combat base as part of Operation Pegasus. Although, despite American claims that they were defending the base at all costs, on 19 June they began the process of dismantling and evacuating the base. During heavy shelling, US Marines attempted to salvage what they could before destroying what remained as they were evacuated. Minor attacks continued before the base was officially closed on 5 July. Marines remained around Hill 689 (one of the hills surrounding the combat base at Khe Sanh) and fighting in the vicinity continued until 11 July until they were finally withdrawn, bringing the battle to a close.
In the aftermath, the North Vietnamese proclaimed a victory at Khe Sanh, while US forces claimed that they had withdrawn, as the base was no longer required. Historians have observed that the battle may have distracted American and South Vietnamese attention from the buildup of Việt Cộng forces in the south before the Tết Offensive. Nevertheless, the US commander during the battle, General William Westmoreland, maintained that the true intention of Tết was to distract forces from Khe Sanh.