U.S. president Richard Nixon visits the Soviet Union.

The president of the United States (POTUS) is the head of state and head of government of the United States. The president directs the executive branch of the federal government and is the commander-in-chief of the United States Armed Forces.

Richard Milhous Nixon was the 37th president of the United States, serving from 1969 until his resignation in 1974. A member of the Republican Party, he represented California in both houses of the United States Congress before serving as the 36th vice president under President Dwight D. Eisenhower from 1953 to 1961. His presidency saw the reduction of U.S. involvement in the Vietnam War, détente with the Soviet Union and China, the Apollo 11 Moon landing, and the establishment of the Environmental Protection Agency and Occupational Safety and Health Administration. Nixon's second term ended early when he became the only U.S. president to resign from office, as a result of the Watergate scandal.

The Union of Soviet Socialist Republics (USSR), commonly known as the Soviet Union, was a transcontinental country that spanned much of Eurasia from 1922 until it dissolved in 1991. During its existence, it was the largest country by area, extending across eleven time zones and sharing borders with twelve countries, and the third-most populous country. An overall successor to the Russian Empire, it was nominally organized as a federal union of national republics, the largest and most populous of which was the Russian SFSR. In practice, its government and economy were highly centralized. As a one-party state governed by the Communist Party of the Soviet Union (CPSU), it was the flagship communist state. Its capital and largest city was Moscow.