Henry Kissinger began an academic career at Harvard after wartime service in the United States Army. His research examined European diplomacy, nuclear strategy, and the problems of maintaining an international balance of power. Nuclear Weapons and Foreign Policy, published in 1957, established him as a prominent strategic commentator. He advised Nelson Rockefeller and other political figures before Richard Nixon appointed him national security adviser in January 1969.

Kissinger helped centralize foreign policy in the White House, using secret negotiations and personal relationships with foreign leaders. His covert visit to Beijing in 1971 prepared Nixon's public opening to China in 1972. He also pursued détente with the Soviet Union, contributing to arms limitation agreements and the effort to manage competition between major powers. In Vietnam he negotiated the Paris Peace Accords of 1973, sharing the Nobel Peace Prize with Le Duc Tho, who declined it.

As secretary of state from September 1973 to January 1977, overlapping initially with his national security position, Kissinger conducted shuttle diplomacy after the Arab-Israeli war of 1973. Negotiated disengagement agreements reduced immediate tensions and increased American influence in the region. His policies also involved support for authoritarian governments and military action with severe civilian consequences. The bombing of Cambodia, United States policy toward Chile, and support for Indonesia around its invasion of East Timor remain major grounds of criticism. Assessments of his statecraft must include these costs alongside negotiations among powerful states.

Kissinger remained influential after leaving office, founding the consulting firm Kissinger Associates in 1982, writing books and memoirs, and advising political and business leaders. His private consulting and continuing access to policymakers drew questions about transparency and the overlap of public influence with commercial interests. He died in 2023. His career made him a defining practitioner of a foreign policy centered on strategic interests and power balances, but also a deeply contested figure. Supporters emphasize diplomatic flexibility and changes in relations with China and the Soviet Union; critics emphasize secrecy, weak accountability, and the treatment of human rights as subordinate to strategic aims. Both the achievements and the coercive methods belong to the record of his work.