When Ho Chi Minh died in mid 1969, Le Duan decided to enshrine public memory of him with the goal of conquering the south, thereby adding an aura of saintliness to the party’s policies and authority. The tightening of domestic social control became increasingly important not only to mitigate war weariness but also to maintain discipline as it became increasingly difficult to dismiss doubts about the Sino-Vietnamese alliance, which had been the cornerstone of victory in the French war. China was uninterested in having a united Vietnam on its southern border and was eager to establish a relationship with the US to give it leverage in relations with the Soviet Union. Although China continued to voice support for Hanoi, it slowly backed away from the war in South Vietnam and instead strengthened its relations with the Cambodian communists who were seeking to overthrow Lon Nol. While the Soviet Union moderated its public support of Hanoi to facilitate relations with the US, it was willing to supply Hanoi with whatever it needed to win the war, gambling on the chance for an alliance with a united Vietnam on the southern border of its Chinese antagonist.
With Nixon’s diplomatic game gathering momentum, Le Duan and Le Duc Tho worried that the time available to achieve their goal in the south was ebbing away. By 1972, there were very few American ground troops in Vietnam, but the Second Republic was looking increasingly formidable. The Paris peace talks were at an impasse. Nixon had conceded the right of the North Vietnamese army to remain in South Vietnam after an agreement, but he rejected Hanoi’s precondi- tion of dismantling the Second Republic. However, 1972 was an American presidential election year, and public opinion in the US and internationally was opposed to continued American involvement in Vietnam. This raised communist hopes that Nixon would be as vulnerable to a major offensive as Johnson had been in 1968 and that he would acquiesce in a Hanoi victory.
In the spring of 1972, North Vietnam mobilized virtually its entire military potential, including strategic reserves, to launch a three-prong invasion of South Vietnam with the goal of winning the war immediately. The South Vietnamese army defeated this invasion with American logistical and air support. Further- more, Nixon mined North Vietnamese harbors and initiated a new bombing campaign against North Vietnam. His escalation of American involvement did not damage American relations with either China or the Soviet Union. Hanoi’s gamble had failed, and, when it became apparent that Nixon would be re-elected, Le Duc Tho signaled to his American negotiating partner, Heinz Alfred (Henry) Kissinger (b. 1923), Nixon’s National Security Advisor, that he no longer demanded the dismantling of the Second Republic before an agreement could be reached.
Le Duc Tho and Kissinger had been conducting secret negotiations separate from the official four-party peace talks, which had never developed beyond issuing propaganda. After the defeat of Hanoi’s spring offensive of 1972, Le Duc Tho was keen for an agreement that would eliminate the US from the war and compromise the Second Republic. The push for an agreement from the American side came from Kissinger’s personal investment in it and from the election of an anti-war congress in the autumn of 1972 that threatened to legislate an end to American involvement in Vietnam when it convened in January 1973.
The agreement drafted by Kissinger and Le Duc Tho provided for the release of American prisoners of war and the end of American military intervention. It allowed the North Vietnamese army to remain in South Vietnam and provided for a political process to supersede the Second Republic with a coalition govern- ment that would include communists and neutralists. It abandoned the aim of preserving a non-communist South Vietnam and discarded the sovereignty of the Second Republic, which was accorded a status equal with the communist Provi- sional Revolutionary Government of South Vietnam.
There were strong public expressions of opposition to this agreement in South Vietnam. The House of Representatives of the National Assembly rejected the political provisions that nullified the Second Republic’s sovereignty. Nguyen Van Thieu announced that he could not accept the agreement without changes. He wanted to initiate direct Hanoi–Saigon negotiations, but the US, just as France had claimed to negotiate for Saigon in 1954, was determined to avoid direct contact between the Vietnamese sides. Nguyen Van Thieu understood that he was powerless to influence the peace talks and trusted Nixon’s assurance that adjustments would be made and that the US would continue to support the Second Republic regardless of any agreement made.
However, when the US proposed changes, Le Duc Tho withdrew a concession previously made that was particularly important to the Americans: separation of the release of American prisoners of war from the issue of releasing political prisoners held by the Second Republic. Nixon needed this concession, for with- out it American prisoners would remain hostage to the disposition of Vietnamese prisoners, which was a difficult and unpredictable issue. With a newly elected Congress that was determined to legislate the end of American involvement in Vietnam scheduled to convene in a matter of weeks, Nixon resorted to a bombing campaign that in a few days destroyed North Vietnam’s air defense capability and persuaded Hanoi to restore the prisoner of war concession, which led to the signing of an agreement in late January 1973 by which the US military presence in Vietnam was terminated within two months.
The political provisions of the Paris Agreement were never implemented, and the war continued in South Vietnam without American participation. After the North Vietnamese defeats in 1972, the Soviet Union provided all that was necessary to rebuild and supply communist forces in South Vietnam. An all- weather road and a pipeline were constructed from North Vietnam through the uplands to a point not far from Saigon, and plans were made for offensive operations to destroy the Second Republic.
Within a year of the agreement, South Vietnam began to experience severe economic and military problems as a result of the 1973 oil embargo crisis and the progressive reduction of US aid. The communist military build-up coincided with American disengagement as Nixon’s political problems and eventual resignation ended the prospect of any further US interest in Vietnamese affairs. The military balance shifted in favor of North Vietnam as South Vietnamese forces suffered shortages of petrol, spare parts, and ammunition. Widespread economic distress led to Saigon street demonstrations in the autumn of 1974. Nguyen Van Thieu’s political career had been based on a trust in the American alliance. As it became apparent that this alliance no longer existed, he was unable to think beyond it and was paralyzed by the looming communist threat, vainly hoping that the US would come to the rescue.
In early 1975, North Vietnamese leaders determined that the US would not return and initiated a campaign that within two months obtained total victory. Days later, fighting broke out between the Vietnamese and the Cambodian communists, who had just gained control of Cambodia with Chinese support. These hostilities were quickly halted, but they foreshadowed another war and demonstrated that American withdrawal had enabled the Sino-Soviet confron- tation to come alive in the region.