During the course of the Cold War, tensions rose and fell many times. One period of relaxation developed in the early 1970s and became known as "Détente," a French word meaning "release of tensions." It was hoped that the new relationship would herald a permanent improvement in relations between the U.S. and Soviet Union, but differences in outlook led to an increasing number of conflicts. The Soviet invasion of Afghanistan in 1979 effectively closed that chapter of the Cold War. The activities of President Ronald Reagan returned tensions to a fever pitch. Soviet relations with the People's Republic of China Détente could probably not have taken place, and certainly wouldn't have assumed the form that it did, without the rift that developed between the world's two primary communist regimes, the Soviet Union and the People's Republic of China (PRC). Despite the fear many Americans had about monolithic communism, the two supposed allies had never been especially close. Joseph Stalin had not backed Mao Tse-tung (Mao Zedong) against the nationalists during World War II, and his insistence that China pay cash for weapons during the Korean War was a source of grievance. Over time, the Soviets decided that Mao was unreliable and that China was a potential rival. When they withdrew their support of China's nuclear weapons program, the Chinese proceeded on their own, exploding their first atomic bomb in 1964 and a Hydrogen Bomb in 1967. By the late 1960s, a million Soviet troops faced a million Chinese troops across the Ussuri River, the easternmost part of the border between those countries. The falling out did not go unnoticed in Washington, D.C. President Richard M. Nixon concluded, despite the origins of his political career in virulent anti-communist activities, that the tension between the Soviet Union and China held promise for the United States. His national security advisor, Henry Kissinger, took the same view. Secret back channels of communication were opened through Pakistan and Romania, sending word to the Chinese that the United States was interested in ending its policy of attempting to politically isolate the PRC. SALT I negotiations were being held in early 1970 with the Soviets while secret talks were going on with the Chinese. Nixon was attempting the Vietnamization of the Vietnam War, which meant withdrawing American troops and replacing them in combat with South Vietnamese. Suddenly, at the end of April, Nixon intensified the conflict by bombing Cambodia to fight the North Vietnamese-supported Khmer Rouge guerillas. The Chinese were publicly indignant and privately cancelled the next round of talks. However, like the Americans, some Chinese leaders saw the advantages of a rapprochement. After an internal struggle within the Chinese Central Committee, those favoring continued contact carried the day. Cold War superpowers breakthrough In April 1971, the breakthrough began. The United States lifted its trade embargo with China, which had been in place since the start of the Korean War. In that same month, a minor incident occurred in Japan, where the world table tennis championships were taking place. A member of the American team mistakenly boarded a bus carrying members of the Chinese team, resulting in the first interaction between team members. The next day, the American team captain proposed to the Chinese captain that the Chinese invite them into their country for a match. With Mao's approval, the invitation was extended and the American athletes became the first from their country to be officially welcomed in decades. With the ice seemingly broken, Kissinger secretly visited Beijing in July 1971 and met Mao and Zhou Enlai. Such ongoing issues as Vietnam and Taiwan were discussed. To advance the process, the Chinese invited Nixon to visit, which he did in February 1972, publicly shaking hands with Mao, and being toasted by Zhou in the Great Hall of the People. Although the trip did not result in many practical steps, it did show that China and the United States had common interests. The prospect of improved relations between its two most formidable enemies caused concern in the Kremlin. A summit between Nixon and Leonid Brezhnev was scheduled, and results from SALT I were finally reached. On May 22, Nixon and Brezhnev signed agreements in Moscow that curbed the arms race for the first time. Four days later, the two men signed the Basic Principles of Relations between the United States and the U.S.S.R. The agreement called for peaceful co-existence, the avoidance of military confrontations, and no claims of spheres of influence. In a move designed to win approval from American farmers, Nixon suggested to the Soviets that they purchase American grain. A month later, a purchase of 400 million bushels of wheat, valued at $700 million, was negotiated, along with favorable credit terms. The price was low and the Soviets quickly purchased a large portion of the U.S. surplus grain reserve, demonstrating that the U.S.S.R. could operate successfully in a capitalist relationship. Vietnam War settlement A settlement to the Vietnam War was one of Nixon's objectives when he established Détente, but it proved a difficult objective. Even with pressure from China and the U.S.S.R., Hanoi did not accept terms until prior to the November elections in October 1972, which was when the North Vietnamese calculated that their best deal would come. But the government in Saigon made the same calculation, concluding that it was too favorable to the North, and refused to sign. After the elections, the talks in Paris broke down, and Nixon resorted to heavy bombing of the North to force an agreement. Talks did resume and the Paris Accords were signed on January 27, 1973. Two months later, the last American soldiers departed from Vietnam. Although the United States pledged continued economic and military support for the South Vietnamese, the Saigon regime survived only another 25 months. An analog of Détente was being pursued by West Germany at the same time. After Social Democrat Willy Brandt came to power in 1969, West Germany began a policy of "Ostpolitik," with the objective of normalizing relations with East Germany. Brandt visited East Germany and signed a non-aggression pact with Moscow as well as a treaty with Poland acknowledging Poland's postwar border on the Oder-Neisse. In December 1972, the two German states signed a treaty of mutual recognition. U.S. and Soviet negotiations In June 1973, Brezhnev visited the United States for a second summit with Nixon. He warned Nixon that America's perceived bias in favor of Israel over Arab interests was putting a strain on Détente in the Middle East. When the October War broke out, it nearly derailed Détente. Both superpowers aided their allies in the region and for a while, nuclear confrontation appeared to be a real possibility. Domestic opposition to Détente grew in 1973. Consideration of "most favored nation" status for the Soviet Union was stalled in Congress over the issue of Soviet treatment of its Jewish population and political dissidents. Senator Henry M. Jackson, of Washington state, worked hard to keep those issues in the public eye. Following Nixon's embattled resignation in August 1974, his successor, Gerald Ford, made it clear to the Soviets that his new administration was still committed to Détente. At a summit with Brezhnev in Vladivostok, held in November, an agreement for a new arms limitation treaty was reached in principle, although it would be a long time before the details could be hammered out. In the summer of 1975, after more than two years of discussion, representatives from Canada, the United States, and 33 European countries met in Helsinki, Finland, to sign an agreement to settle postwar borders. The final act of the Conference on Security and Cooperation in Europe consisted of three "baskets." The first consisted of practical measures regarding security. Existing borders were confirmed and the parties pledged peaceful settlements of disputes. The second dealt with cooperation in terms of trade, culture, science and industry. The third addressed humanitarian concerns and called for free movement of peoples and circulation of ideas. The United States and the U.S.S.R. viewed the three baskets differently. The Soviets were happy with the first two and considered the third a public relations exercise, which they could ignore within their own borders. Although it was signed on August 1, 1975, the U.S. was not happy to recognize Soviet hegemony in Eastern Europe, but considered that, on balance, the treaty served its interests. SALT II finally produced an accord in June 1979. President Jimmy Carter presented it to the Senate for approval, but opposition delayed ratification. The atmosphere turned very chilly after the Soviet invasion of Afghanistan in December, and in January, Carter asked the Senate to suspend consideration until a more opportune time. That time never came. When Carter was succeeded by Ronald Reagan, the presidency passed to someone who had never approved of the concept of Détente and who brought about the largest peacetime military build-up in the nation's history during his first years in office. Golda Meir, prime minister of Israel, once remarked, "I don't know why you use a fancy French word when there's a good English phrase for it — cold war." Certainly in retrospect, Détente seems to have just been the continuation of the Cold War by other means. Nevertheless, it demonstrated that permanent conflict was not the only option, and that accommodation could lead to agreement. The Cold War might resume, but it would never be the same.