(1884 – 1972) Elected vice-president in 1944 when Franklin D. Roosevelt won a fourth consecutive presidential term, Truman became president when Roosevelt died in April 1945. Within months he had made pivotal foreign-policy decisions: at the Potsdam Conference he and Allied leaders agreed to prosecute German leaders for war crimes committed during the Second World War; and, in August, he approved the dropping of atomic bombs on Japanese cities Hiroshima and Nagasaki, bringing an end to the Second World War.

Early in the Cold War, his administration adopted the Truman Doctrine, which developed into the policy of “containment” to halt Soviet expansion. One aspect of the Doctrine was the Marshall Plan, an economic recovery program for European nations, and the North Atlantic Treaty Organization (NATO), a military alliance designed to protect Western Europe from Soviet aggression.

Truman began the 1948 presidential campaign as an underdog to Republican nominee Thomas Dewey. However, he defeated Dewey, proving wrong experts and a premature headline in the Chicago Tribune: “Dewey Defeats Truman.” In June 1950, communist North Korea invaded South Korea, prompting Truman to send United States forces to the region to protect South Korea. Led by General Douglas MacArthur, United Nations’ (UN) troops brought most of South Korea under UN control by October.

Truman is most often remembered for developing a civil-rights agenda, issuing executive orders banning discrimination in the civil service and in the armed forces, and for his phrase, “The buck stops here,” meaning ultimate responsibility rests with the president.