Detente emerged as the guiding framework of relations between the USSR and United States in the early 1970s. It origins were varied. First, some leaders in both countries had been alarmed at how close the two sides came to full-scale war in the Cuban Missile crisis of 1962, and had advocated a policy that ratcheted down some of the tensions between the two powers. Closely related to this idea was the knowledge that, with the accumulation of nuclear weapons on both sides, a war between the two nations would lead to their annihilation. This principle, known as Mutually Assured Destruction, was essential to the strategic balance on which detente theoretically depended. Finally, detente was rooted in the massive military spending that both sides engaged in, often to the detriment of social programs, as well as the US desire to extricate itself from the struggle in Vietnam.
The policy is most often associated with the Nixon presidency under the guidance of Henry Kissinger, which sought increased dialogue with the Soviets. Kissinger argued that the United States could achieve strategic goals without the destruction of the Soviet Union, and could even broker trade arrangements with the other superpower as long as these arrangements were linked to concessions. To this end, the United States sought improved relations with China, which alarmed Soviet leadership and made them more willing to bargain. In Europe, it was associated with leaders such as West Germany's Willy Brandt, whose Ostpolitik approach emphasized dialogue with the communist bloc.
Detente is most often associated with arms limitation agreements, most conspicuously SALT (Stategic Arms Limitation Treaty) I and SALT II. When Richard Nixon resigned from office, however, support for detente waned, and the Senate refused to ratify SALT II. Detente was also compromised during Jimmy Carter's presidency by Soviet nuclear buildups in Eastern Europe and especially by the invasion of Afghanistan in 1979. When Ronald Reagan entered office, he described detente as immoral in that it countenanced Soviet human rights abuses. Styling the USSR an "evil empire," he embarked on an aggressive course of action that featured massive military buildups and strident anti-Soviet rhetoric. Detente, always a fragile state of affairs, had come to an end.