In early 1965, there were 22,000 US Special Forces advisers, pilots, and support personnel in South Vietnam assisting the Republic of South Vietnam in the war against the communist National Liberation Front insurgents aka Viet Cong (VC), and their backers in North Vietnam. The situation in South Vietnam steadily deteriorated over the previous two years and the chaos reached a crescendo in February 1965. The Army of the Republic of South Vietnam (ARVN) was recently defeated in two conventional battles against the VC and regular North Vietnamese Army (NVA). Also the civilian government of South Vietnam endured a successful coup by the ARVN Army Chief of Staff, Gen Nguyen Khanh and his Buddhist supporters, only to be immediately followed by another failed coup by communist sympathizers on the Armed Forces Council (The Vietnamese version of the Joint Chiefs of Staff). Furthermore, the South Vietnamese village pacification program was recognized as a complete failure in February. Additionally, Viet Cong terror bombings became increasing common in South Vietnam’s major cities. But the final straw was the attack on Pleiku Air Base which killed eight Americans, wounded 128 others and destroyed 20 aircraft in the first large scale attack directed solely at Americans.
In response to the chaos, on 2 March 1965, President Lyndon Johnson authorized Operation Rolling Thunder, a sustained bombing campaign against the Viet Cong’s supply routes aka the “Ho Chi Minh Trail”, and military and industrial targets inside North Vietnam. Rolling Thunder was a major escalation to the war. The operation was scheduled to last eight weeks; it would go on for three years.
In order to protect the Rolling Thunder airbases from further Pleiku style attacks, the Military Assistance Command – Vietnam commander, Gen. William Westmoreland, requested American ground combat troops. The first of these arrived on 8 March 1965 when two battalions of US Marines landed on the beach at Danang, where they assumed security of the US airbase there. They could have flown directly to the airbase, but Westmoreland thought it more dramatic for the cameras if they landed on the beach like their fathers did in the Pacific War.
95,000 more American troops followed over the course of 1965.