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.
1975 Spring Offensive
At 4:58 a.m on 30 April, U.S. Ambassador Martin boarded a helicopter and departed from the US Embassy, Saigon on one of the last American evacuation flights. At 07:53 the last U.S. Marines were lifted from the roof of the U.S. Embassy. At 10:24 a.m. President Minh ordered all South Vietnamese forces to cease fighting. Later Minh would be escorted to a radio station, from which he declared the unconditional surrender of his government. Around noon, a PAVN tank, number 390, crashed through the gates of the Independence Palace. A crewman from the 843, which rammed into the side gate and got stuck, jumped out, ran up the steps, carrying the flag of the Provisional Revolutionary Government. A Western reporter on the scene asked the soldier his name and the man replied, "Nguyễn Văn Thiệu."