John Foster Dulles built his career in international law and Republican foreign-policy circles before becoming Dwight D. Eisenhower's secretary of state in 1953. A lawyer with Sullivan and Cromwell, he advised on international finance and attended the Paris Peace Conference in 1919. He later worked on international organization and briefly served as a United States senator from New York in 1949.

Before entering Eisenhower's cabinet, Dulles helped negotiate the 1951 peace treaty with Japan and the accompanying security relationship with the United States. As secretary he sought to contain communist power through alliances, economic pressure, and the threat of nuclear retaliation. His association with "massive retaliation" reflected the administration's attempt to deter war while limiting the cost of maintaining large conventional forces.

Dulles helped organize the Southeast Asia Treaty Organization and supported security arrangements in the Middle East. His diplomacy addressed crises in Indochina, the Taiwan Strait, Berlin, and Hungary. Strong anticommunist language could raise expectations that Washington would reverse Soviet control, although the administration avoided direct military intervention during the Hungarian uprising of 1956. At Suez that year, the United States opposed the British, French, and Israeli attack on Egypt, demonstrating that Cold War partnership did not eliminate conflicts among allies.

He worked closely with the Central Intelligence Agency, directed by his brother Allen, during covert interventions in Iran and Guatemala. These operations served immediate American strategic objectives but undermined governments and shaped disputes over American power. Dulles was an influential partner of Eisenhower, who retained final control of major decisions. Illness forced him to resign in April 1959, shortly before his death. He left an alliance network and a policy of containment that fostered both deterrence and resentment of American intervention.