(b. May 8, 1884; d. December 26, 1972) Thirty-third president of the United States (1945–1953).

Harry Truman served as president of the United States from April 12, 1945, to January 20, 1953, a time of pivotal importance in America's relations with the world. Wars—past, present, and future, hot and cold—heavily influenced his point of view and dominated his presidency.

The impact of war began early and continued to be a major feature of Truman's life. As a young man, he served for six years in the Missouri National Guard. Volunteering for World War I in 1917, he became the captain of an artillery battery and participated in the drive that ended the war. Following that war, he championed military preparedness as an officer in the army reserve for two decades and as a United States senator, beginning in 1935.

World War II influenced Truman in major ways. It strengthened his conviction that the...