The Vietnam War (Vietnamese: Chiến tranh Việt Nam), also known as the Second Indochina War, and in Vietnam as the Resistance War Against America (Vietnamese: Kháng chiến chống Mỹ) or simply the American War, was a conflict that occurred in Vietnam, Laos, and Cambodia from 1 November 1955[A 1] to the fall of Saigon on 30 April 1975, with U.S. involvement ending in 1973. It was the second of the Indochina Wars and was officially fought between North Vietnam and the government of South Vietnam. The North Vietnamese army was supported by the Soviet Union, China, and other communist allies; the South Vietnamese army was supported by the United States, South Korea, the Philippines, Australia, Thailand and other anti-communistallies. The war is considered a Cold War-era proxy war by some US perspectives. The war would last approximately 19 years and would also form the Laotian Civil War as well as the Cambodian Civil War, which resulted in all three countries becoming communist states in 1975.
Beginning in 1950, American military advisors arrived in what was then French Indochina.[A 3] Most of the funding for the French war effort was provided by the U.S. The Việt Cộng, also known as Front national de libération du Sud-Viêt Nam or NLF (the National Liberation Front), a South Vietnamese communist common front aided by the North, fought a guerrilla war against anti-communist forces in the region, while the People's Army of Vietnam (PAVN), also known as the North Vietnamese Army (NVA), engaged in more conventional warfare, and had launched armed struggles from 1959 onward. U.S. involvement escalated in 1960 under President John F. Kennedy, with troop levels gradually surging under the MAAG program from just under a thousand in 1959 to 16,000 in 1963.
By 1964 there were 23,000 U.S. troops in Vietnam, but this escalated further following the 1964 Gulf of Tonkin incident, in which a U.S. destroyer was alleged to have clashed with North Vietnamese fast attack craft. In response, the Gulf of Tonkin Resolution gave President Lyndon B. Johnson broad authorization to increase U.S. military presence, deploying ground combat units for the first time and increasing troop levels to 184,000. Every year onward there was significant build-up despite little progress, with Robert McNamara, one of the principal architects of the war, beginning to express doubts of victory by the end of 1966. U.S. and South Vietnamese forces relied on air superiority and overwhelming firepower to conduct search and destroy operations, involving ground forces, artillery, and airstrikes. The U.S. conducted a large-scale strategic bombing campaign against North Vietnam. After the Tet Offensive of 1968, the Army of the Republic of Vietnam (ARVN) unconventional and conventional capabilities increased following a period of neglect and became modeled on heavy fire-power focused doctrines like US forces. Operations crossed international borders: bordering areas of Laos and Cambodia were used by North Vietnam as supply routes and were heavily bombed by U.S. forces.
Various names have been applied to the conflict. Vietnam War is the most commonly used name in English. It has also been called the Second Indochina War and the Vietnam Conflict.
As there have been several conflicts in Indochina, this particular conflict is known by the names of its primary protagonists to distinguish it from others. In Vietnamese, the war is generally known as Kháng chiến chống Mỹ (Resistance War Against America), but less formally as 'Cuộc chiến tranh Mỹ' (The American War). It is also called Chiến tranh Việt Nam (The Vietnam War).