History Causes

The U.S. adopted containment as official policy after WWII

U.S. leaders believed that if one Southeast Asian country fell to communism, others would follow.

Presidents who all justified aid, advisors, and eventually full military intervention in Vietnam under the logic of containment.

"You have a row of dominoes set up, you knock over the first one, and what will happen to the last one is the certainty that it will go over very quickly."

Ngo Dinh Diem

Diem ran South Vietnam as a dictatorship, filled government posts with family members.

Because Diem's regime lacked legitimacy, the U.S. felt it had to step in with more financial and military support to keep South Vietnam stable.

Forcing villagers into fortified villages to cut them off from Viet Cong influence. Alienated the population and increased support for the Viet Cong, making the war harder to win.

When Diem was assassinated, tacitly supported by the U.S.

South Vietnam became even more unstable, dragging the U.S. further into direct involvement. The U.S. felt it had no choice but to take greater control of the war effort, leading to Johnson's escalation after 1964.

Gulf of Tonkin, off the coast of North Vietnam.

August 1964

Alleged attacks by North Vietnamese torpedo boats on U.S. destroyers (USS Maddox and USS Turner Joy).

The resolution which gives President Johnson broad powers to escalate U.S. military involvement in Vietnam without a formal declaration of war.

The Gulf of Tonkin Incident as a justification for escalating U.S. involvement in Vietnam.