What was the primary focus of the Truman Doctrine?

The primary focus of the Truman Doctrine was to provide aid to countries that were threatened by the spread of communism. This doctrine, announced by President Harry S. Truman in 1947, represented a significant shift in U.S. foreign policy, moving from isolationism to a more interventionist approach. Truman outlined that the U.S. would support free peoples resisting subjugation, specifically in Europe and later other regions, to combat the influence of the Soviet Union and prevent the expansion of communism. The doctrine was a foundational element of U.S. strategy during the Cold War, leading to various forms of economic and military assistance to nations perceived as vulnerable to communist influence.