2. **Political Career**: Truman served as the 33rd President of the United States from April 12, 1945, to January 20, 1953. He assumed office upon the death of Franklin D. Roosevelt and won a full term in his own right in 1948.

3. **Dropping the Atomic Bomb**: One of Truman’s most controversial decisions was authorizing the use of atomic bombs against Japan during World War II. The first bomb was dropped on Hiroshima on August 6, 1945, and the second on Nagasaki three days later.

4. **Domestic Policies**: As president, Truman initiated several significant domestic programs including the Marshall Plan to aid European recovery after WWII, supported civil rights with executive orders that began integrating the military and federal workforce, and established the CIA and National Security Council.

5. **Truman Doctrine & Policy**: The Truman Doctrine was a foreign policy initiative in 1947 that aimed to contain communism worldwide. This policy led to significant U.S. involvement in the early stages of the Cold War, notably in Greece and Turkey.

6. **Post-Presidency**: After leaving office, Truman wrote his memoirs, which were published in two volumes: “Years of Trial and Triumph” (1946) and “Years of Decision” (1950). He lived a relatively private life afterward, passing away on December 26, 1972.