Truman Doctrine - Cold War Begins
President Truman's address to Congress marked the formal beginning of the Cold War
March 12, 1947
A Line Drawn Against Communism
On March 12, 1947, President Harry S. Truman stood before a joint session of Congress and made a bold declaration: the United States would support free peoples around the world who were resisting communist takeover. He was speaking specifically about Greece and Turkey, both of which faced serious threats from communist movements backed by the Soviet Union. Britain had told the U.S. it could no longer afford to support those countries militarily. Truman asked Congress for $400 million in aid. Congress approved it, and the Truman Doctrine was born — one of the defining policies of the Cold War.
The Logic Behind the Doctrine
Truman's team, especially diplomat George Kennan, believed that communism spread best where there was poverty, instability, and despair. The solution was to build up the economies and defenses of vulnerable countries so that communism had no foothold. This policy became known as "containment" — the idea that the U.S. should not try to roll back communism where it already existed, but should prevent it from spreading further. The Truman Doctrine worked hand in hand with the Marshall Plan, which provided massive economic aid to rebuild war-torn Western Europe and keep it out of the Soviet orbit.
A Policy That Shaped Decades
The Truman Doctrine set a precedent that American presidents followed for the next four decades. It justified U.S. involvement in Korea, Vietnam, and countless other conflicts around the world. Critics argued that it led America into costly and unnecessary wars. Supporters said it was essential for stopping the spread of an authoritarian ideology. When the Soviet Union finally collapsed in 1991, many credited the containment strategy with having worked. The Truman Doctrine was one of the most consequential foreign policy decisions in American history, shaping the world order for a generation.