The Truman Doctrine is a set of principles of U.S. inland policy created on March 12, 1947 by President Harry S Truman. In this, Truman declared that the United States, as leader of the "free world," must support capitalism worldwide and fight against communism. The approach was conceived with the help of George Marshall and Dean Acheson, two influential associates of Truman, which generalized his hopes for Greece and Turkey into a doctrine applicable throughout the world. The Soviet Union was clearly at the heart of Truman's thoughts, but it was never directly mentioned in his speech. Truman was attempting to solve Eastern Europe's instability while making sure that communism would not spread to nations like Greece and Turkey.
Many Americans were against the Truman Doctrine, because they thought that the United States could not handle the situation by itself.
The Truman Doctrine represented the harsh aspect of containment policy, and the Marshall Plan was the soft side. The declaration of the Truman Doctrine served to inhibit the formation of coalition governments that included communists.
Truman fought to promote anti-Communism in Greece and Turkey. He put forth his policy of containment in order to obstruct Communism and stimulate a free and just government that would protect basic human rights. The Truman Doctrine combined political, economic, and strategic elements. Truman strived to strengthen the non-Soviet world by encouraging political liberty and economic prosperity; he also made freedom the centerpiece of the American postwar foreign policy.