The Vietnam War

French Indochina was part of the French empire in Southeast Asia

The domino theory was a theory put forward by President Eisenhower in the 1950s. It theorised that communism would spread throughout Asia as each country is influenced by its neighbour.

After Japan's defeat in WW2, Vietnamese Communists (Vietminh) led by Ho Chi Minh, took control of North VIetnam and declared its independence. France tried to take back their former colony and a war broke out between them and the Vietminh.

In Geneva, the country was divided into North and South Vietnam until the elections took place.

In 1954, the US prevented elections from taking place to contain communist as they believed that China and the USSR were trying to spread it.

In 1955, the US helped Ngo Dinh Diem to set up the Republic of South Vietnam despite his corruption and the Vietnamese People's hatred towards him due to his anti-communism.

In the 1950s, the US supplied him with $1.6 bn in aid.

He was overthrown by his army in November 1963.

Support increased due to actions of anti-communist governments. 

Viet Cong sent supplies and reinforcements to Guerilla fighters who attacked American Air Force and supply bases. 

By 1962, Kennedy was sending military "advisors". 

Kennedy was assassinated in 1963. His successor, Lyndon Johnson, was prepared to commit to full-scale conflict to prevent the spread of communism.

This allowed the President to do anything to assist "any member or protocol state of the Southeast Asia Collective Defense Treaty", including the use of armed forces.

It was passed on August 7th 1964 as a result of the Gulf of Tonkin incident.

During the incident, South Vietnamese torpedo boats were seen approaching a US ship. As a result, the US fired three warning shots, but when they continued to approached, Maddox, the US ship, fired on them. It resulted in major damage to South Vietnam torpedo boats and the deaths of some on board while the US ship Maddox received minor damage and zero casualties or injuries.