History of the United States (1964–1980)
The growing Watergate scandal was a major disaster for Nixon, eroding his political support in public opinion and in Washington. However he did manage to secure large-scale funding for South Vietnam, much of which was wasted. The United States withdrew its troops from Vietnam before the Paris Peace Accords in 1973. However, Watergate resulted in significant Democrat gains in the 1974 midterm elections and when the new 94th Congress convened the following January, it immediately voted to terminate all aid to South Vietnam in addition to passing a bill forbidding all further US military intervention in Southeast Asia. President Ford was against this, but as Congress had a veto-proof majority, he was forced to accept. South Vietnam rapidly collapsed as the North invaded it in force, and Saigon fell to the NVA on April 30, 1975. Later nearly one million Vietnamese managed to flee to the U.S. as refugees. The impact on the U.S. was muted, with few political recriminations, but it did leave a "Vietnam Syndrome" that cautioned against further military interventions anywhere else. Nixon (and his next two successors Ford and Carter) had dropped the containment policy and were not willing to intervene anywhere.
National Security Action Memorandum 273
The immediate response of the U.S. government to its sudden realization that the political and military situation in South Vietnam was not good was to expand the U.S.'s role in the Vietnam War. NSAM 273 had defined the "central object" of the U.S. "to assist the people and Government [of South Vietnam] to win their contest against the externally directed and supported Communist conspiracy." Escalating the U.S. objectives, on January 22, 1964, the Joint Chiefs of Staff sent McNamara a memo declaring "victory" to be the U.S. objective and recommending that the U.S. "put aside many of the self-imposed restrictions which now limit our efforts and undertake bolder actions which may embody greater risks." On 30 January another "coup d'etat" in Saigon emphasized to the U.S. policy makers the instability of the South Vietnamese government. Disarray in Saigon was accompanied by policy wars in Washington between the Departments of State and Defense and within the Department of Defense. A series of decisions on Mar. 8, 1965 to escalate U.S. involvement in Vietnam was the end result.