The priorities of the Nixon presidency lay not in domestic social or economic policies—which were simply the means to the end—but in reelection through creation of a majority coalition. What really interested Nixon was statecraft, the application of American power and diplomatic influence to regional and global problems.
The key problem for his presidency clearly would be the Vietnam War. It had driven his predecessor from office, and if it were not resolved in a way that could be turned to political advantage, it would drive him from office as well. Two months after Nixon assumed the presidency, American combat deaths exceeded thirty-six hundred, and there seemed no end in sight. Nixon was in a dilemma, for during the campaign he had said that he had a "secret plan" to end the war but could not divulge it because it might upset the Paris peace negotiations. If his plan involved escalation, Democrats could charge that he was abandoning attempts to reach a peaceful solution and could point to mounting American casualties and prisoners of war. If he negotiated a solution that led to the fall of the government in Saigon, Democrats could charge that he had abandoned an ally. Nixon had to find a way to cut American commitments while preserving the non-Communist government in South Vietnam—at least for a "decent interval" so that the overthrow of the regime could not be blamed on the United States.
Nixon, his national security adviser Henry Kissinger, and Secretary of Defense Melvin Laird settled on an approach with several elements. First, the Laird policy for "Vietnamization" was adopted. Responsibility for fighting would be turned over to the Vietnamese, in order to reduce American casualties. Gradually American forces would be withdrawn. This would buy time on the home front. Second, a variant of the "madman" approach in international relations would be adopted. The administration would warn the North Vietnamese that unless they settled soon they would be subjected to carpet bombing of cities, mining of harbors, and even the spread of radioactive debris to halt infiltration of the South. Irrigation dikes would be destroyed and forests defoliated. Third, Nixon and Kissinger would apply the principle of "linkage" in dealing with the Soviet Union: the arms and trade agreements to be proposed to the Soviets (see below) would require a quid pro quo—Moscow would have to pressure Hanoi to agree to a settlement.
The Vietnam policy failed. Nixon announced the withdrawal of a half million troops, and by May 1972 no American forces were on combat missions. By January 1973, only twenty-five thousand American troops remained in Vietnam. The level of fatalities and injuries dropped. But the combat effectiveness of the South Vietnamese did not improve. The invasion of Laos by South Vietnamese forces not only was ineffective but turned into a rout, leaving little doubt that they would be no match for the North Vietnamese.
The escalation of the air war also failed. In mid-March 1969 a secret bombing campaign against Cambodia began; it was kept secret from Congress and the American people for two years. The Ho Chi Minh Trail in Laos, which supplied the Communists in the south (Vietcong), was also bombed, and the number of targets in South Vietnam was increased. In the spring of 1970 bombing was renewed over North Vietnam (reversing a halt ordered by President Johnson in 1968) in the industrial complex between Hanoi and Haiphong.
Ground actions were also stepped up. Incursions into Laos doubled in 1969. South Vietnamese and American troops made incursions into Cambodia in April and May 1970 to clear out enemy units and headquarters in the "Parrot's Beak" salient, which was dangerously close to Saigon. The main effect of the intervention was to drive Cambodian Communist units to the west, into the heart of Cambodia, where together with their North Vietnamese allies they prepared for the overthrow of the existing pro-American regime. Not only was this policy unsuccessful militarily, but it triggered renewed antiwar protests at home. At a demonstration on 4 May at Kent State University, National Guardsmen killed four protesters. A huge antiwar demonstration was then held in Washington, D.C., between 6 and 9 May, at which Richard Nixon, in the middle of the night, visited the Lincoln Memorial to talk with some of the protesters about college football, campus life, and other trivialities, not reaching their concerns about the war and the direction of American foreign policy.
North Vietnam meanwhile had its own plans. It prepared for a general offensive in 1972, timed to put pressure on the Nixon administration to settle the war on Hanoi's terms prior to the presidential elections. In view of the failure of Vietnamization, neither the Soviet Union nor North Vietnam had any intention of giving to American negotiators in Paris what the South Vietnamese could not win on the battle-field. The linkage tactic would not work.
Nixon fared better in the home-front battle for public opinion. Although there were large antiwar demonstrations, including the November 1969 "March on Washington," the May 1970 Cambodia protests, and the April 1971 "Mobilization Against the War," there was rising support for Nixon's policies. Escalation of the bombing and the withdrawal of American combat forces resulted in a significant increase in presidential-approval ratings.
Peace negotiations dragged on throughout Nixon's first term. Even before entering office, Nixon had passed word to the South Vietnamese that he could probably get better peace terms for them than the Johnson administration. But in 1969 and 1970, each side rejected the other's eight-point peace plan. In November 1971 peace talks were suspended by Washington, and in 1972 each side in turn temporarily suspended its participation in the talks.
Talks resumed on 19 July 1972, and by the end of the summer two things had become clear to the negotiators: American escalation of the bombing could not induce the North Vietnamese to settle for terms that would require their withdrawal from the South, and no pressure from either the Soviet Union or the People's Republic of China could induce the North Vietnamese to settle. But although the North Vietnamese had made major gains with their spring offensive, they had not achieved all their objectives, and they had been dislodged from several of the cities they had taken. Both sides, having played their hands, were now ready for a settlement.
Henry Kissinger and his North Vietnamese counterpart, Foreign Minister Le Duc Tho, reached an agreement on terms on 12 October 1972, and two weeks later Kissinger announced, "Peace is at hand." But when the South Vietnamese objected to the terms (chief of which involved a cease-fire in place, recognition of the territory controlled by each side, and preparation for a political settlement involving sharing of power), Nixon held up the agreement. Instead, he ordered massive bombing of North Vietnam after his reelection. The purpose seems to have been twofold: to convince the North Vietnamese that the United States would not allow the regime in Saigon to be overthrown and to convince the South Vietnamese that secret commitments (made in an exchange of letters between Nixon and President Nguyen Van Thieu) would be honored after American forces withdrew under terms of the proposed agreement. After more negotiations, an agreement was concluded on 27 January 1973, paving the way for an end to American participation in the war and an exchange of prisoners.
Nixon's commitments to Thieu could not be kept. Congress had imposed restrictions on presidential war-making powers in Southeast Asia, beginning in 1970 with the Cooper Amendment, which provided that no combat troops could be sent to Laos or Thailand, followed by the Cooper-Church Amendment (1970), which prohibited the reintroduction of ground forces into Cambodia, and culminating with passage of the Eagleton Amendment, which called for a halt in all American land, sea, and air military operations in Laos, Cambodia, and Vietnam after 15 August 1973. Any attempt by Nixon or his successors to use American armed forces to guarantee the survival of the Saigon regime would be illegal. Moreover, the War Powers Resolution, passed by Congress over Nixon's veto in 1973, required any American president to obtain congressional approval within sixty days for any military action; this presented yet another problem in shoring up the South Vietnamese government. The Nixon commitments to Thieu were therefore not honored by the Ford administration in 1975, which resulted in the reunification of North and South Vietnam under Communist rule.