After US troops withdrew from South Vietnam, North Vietnam won the war and unified Vietnam into a communist regime.
Explanation:
Campaigning under the slogan "peace with honor", Richard M. Nixon won the 1968 presidential election. In 1969, Nixon launched his own plan to end US participation in the Vietnam War. President Nixon outlined a plan called Vietnamization, which consisted of a process to withdraw US troops from Vietnam, while fighting was returning to the South Vietnames. The withdrawal of US troops began in July 1969. President Nixon also expanded the war to other countries, such as Laos and Cambodia. This movement caused thousands of protests, especially on university campuses. The peace talks began in Paris on January 25, 1969.
As part of this plan, US troops were withdrawn little by little. Nixon complemented this approach with efforts to alleviate global tensions through diplomatic rapprochement with the Soviet Union and the People's Republic of China. In Vietnam, the war went on to smaller operations aimed at attacking the logistics of North Vietnam. This was positively welcomed by the protest movement against the war. But the news of a massacre of 347 Vietnamese civilians from the south by US soldiers in My Lai on March 18, 1968 caused this movement to get back on its feet.
The tension increased even more when the US started bombing North Vietnamese bases on the border. In 1970, with ground forces attacking Cambodia, it seemed that the war was spreading instead of ending. Public opinion collapsed in 1971 with the publication of the Pentagon Papers, a top secret report detailing the American mistakes in Vietnam since 1945, as well as the lies exposed about the incidents in the Gulf of Tonkin, the detailed participation of the US in the war and the revelation of the secret bombing of Laos. These documents posed a very bleak picture for the prospects for US victory.
Despite the incursion into Cambodia, Nixon had begun the systematic withdrawal of US forces, reducing the number of troops to 156,800 in 1971. That same year, the South Vietnamese Army began Operation Lam Son 719 with the objective of cutting the HoChi Minh route in Laos. In what was seen as a dramatic failure of the Vietnamization, the ARVN forces were defeated and forced to retreat to the border.
Later, new problems emerged. When the US had withdrawn most of their troops from Vietnam, the North Vietnamese organized another massive assault, known as the Easter Offensive, on March 30, 1972. Troops from North Vietnam crossed the demilitarized zone at the 17th parallel and invaded South Vietnam. This offensive could only be rejected with the support of US air power, with the famous Operation Linebacker, which took place from May 9 to October 23, 1972.
On January 27, 1973, as a result of the peace talks in Paris, the ceasefire agreement was reached. The last American troops left Vietnam on March 29, 1973, knowing that they were leaving a weak South Vietnam, which would not be able to withstand another attack by the communists of North Vietnam.
In fact, after the US had withdrawn all their troops, the battles continued in Vietnam. At the beginning of 1975, North Vietnam advanced strongly towards the south and overthrew its government. South Vietnam officially surrendered to North Vietnam on April 30, 1975. On July 2, 1976, Vietnam reunified as a communist country: the Socialist Republic of Vietnam.
