Richard Nixon began his national political career after wartime naval service, winning election to the House of Representatives from California in 1946. The Alger Hiss investigation established his reputation as an aggressive anticommunist. Elected senator in 1950, he became Dwight Eisenhower's running mate in 1952. As vice president from 1953 to 1961 he travelled extensively, represented the administration abroad and increased the office's visibility. He lost the 1960 presidential and 1962 California gubernatorial elections.

Nixon returned to electoral politics and won the presidency in 1968, promising order at home and an end to the Vietnam War. His administration pursued Vietnamization, reducing American ground forces while expanding bombing and operations into Cambodia. The widening conflict intensified opposition and caused extensive suffering. The Paris agreement of 1973 preceded the withdrawal of remaining American combat troops but did not secure a lasting peace in Vietnam. Nixon's 1972 visit to China opened a major diplomatic channel, while agreements with the Soviet Union advanced détente and nuclear arms limitation. These initiatives reflected a pragmatic pursuit of power relationships across ideological divisions.

Domestic measures included creation of the Environmental Protection Agency, wage and price controls and the ending of dollar convertibility into gold. His administration oversaw substantial school desegregation while cultivating a political strategy that appealed to voters resistant to rapid social change. Conflicts over executive authority, surveillance and the treatment of opponents accompanied these achievements. Nixon won a landslide reelection in 1972, but the break-in at Democratic headquarters in the Watergate complex and the subsequent cover-up increasingly dominated his second term.

Investigations uncovered abuses by campaign and administration personnel, and White House tapes supplied evidence. Nixon dismissed special prosecutor Archibald Cox during the Saturday Night Massacre in 1973. After the Supreme Court ordered release of subpoenaed recordings, evidence of his participation in obstructing the investigation destroyed remaining congressional support. Facing impeachment, he resigned effective 9 August 1974, the only American president to do so. Gerald Ford later pardoned him. Nixon spent subsequent years writing and commenting on foreign affairs. His diplomacy remains inseparable from the abuses that ended his presidency.