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.
History of Vietnam since 1945
Although the Tết Offensive was a catastrophic military defeat for the Việt Cộng, it was a stunning political victory as it led many Americans to view the war as unwinnable. U.S. President Richard Nixon entered office with a pledge to end the war "with honor." He normalized US relations with China in 1972 and entered into détente with the USSR. Nixon thus forged a new strategy to deal with the Communist Bloc, taking advantage of the rift between China and the Soviet Union. A costly war in Vietnam begun to appear less effective for the cause of Communist containment. Nixon proposed "Vietnamization" of the war, with South Vietnamese troops taking charge of the fighting, yet still receiving American aid and, if necessary, air and naval support. The new strategy started to show some effects: in 1970, troops from the Army of the Republic of Vietnam (ARVN) successfully conducted raids against North Vietnamese bases in Cambodia (Cambodian Campaign); in 1971, the ARVN made an incursion into Southern Laos to cut off the Ho Chi Minh trail in Operation Lam Son 719, but the operation failed as most high positions captured by ARVN forces were recaptured by North Vietnamese artillery; in 1972, the ARVN successfully held the town of An Lộc against massive attacks from North Vietnamese regulars and recaptured the town of Quảng Trị near the demilitarised zone (DMZ) in the center of the country during the Easter Offensive.