Between the late 1960s and the late 1970s, there was a thawing of the ongoing Cold War between the United States and the Soviet Union. This détente took several forms, including increased discussion on arms control. Although the decade began with vast improvements in bilateral relations, by the end of the decade events had brought the two superpowers back to the brink of confrontation.
Two decades after the Second World War, Soviet-American tension had become a way of life. Fears of nuclear conflict between the two superpowers peaked in 1962 in the wake of the Cuban Missile Crisis, paving the way for some of the earliest agreements on nuclear arms control, including the Limited Test Ban Treaty in 1963. Although these agreements acted as important precedents, the U.S. escalation of the war in Vietnam increased tensions again and served to derail any efforts in the mid-1960s to pursue further arms agreements. By the late 1960s, however, both countries had several concrete reasons for resuming arms talks. The ongoing nuclear arms race was incredibly expensive, and both nations faced domestic economic difficulties as a result of the diversion of resources to military research. The emergence of the Sino-Soviet split also made the idea of generally improving relations with the United States more appealing to the USSR. The United States faced an increasingly difficult war in Vietnam, and improved relations with the Soviet Union were thought to be helpful in limiting future conflicts. With both sides willing to explore accommodation, the early 1970s saw a general warming of relations that was conducive to progress in arms control talks.