From Wikipedia

Cold War
Episode Sixteen

Détente (1969–1975) Nixon builds closer relations with China and the USSR, hoping to leverage an honourable US exit from Indochina. The Soviet Union is fearful of a US-Chinese alliance, but summits between Nixon and Brezhnev lead to a relaxation of tensions and concrete arms control agreements. Willy Brandt's Ostpolitik strategy also normalises West German relations with East Germany, the USSR and Poland. Although deeply unpopular domestically, US bombing of Cambodia and Hanoi succeeds in bringing North Vietnam to the negotiating table, leading to the Paris Peace Accords in 1972. Deeply resented by South Vietnam, the Accords ultimately fail to prevent Saigon's fall three years later. In 1975 reapproachment continued with the Helsinki Accords, which enshrined human rights and territorial integrity, and the symbolic Apollo–Soyuz Test Project. Interviewees include Melvin Laird, Valeri Kubasov, Winston Lord, John Ehrlichman and Gerald Ford. The pre-credits scene shows a Soviet cartoon demonstrating the futility of the arms race.