Doctrine enunciated by U.S. President Harry S Truman in a speech to Congress on March 12, 1947, proclaiming a U.S. commitment to aid noncommunist countries to resist expansion by the Soviet Union. Truman, announcing this plan to contain communism, declared that American policy was “to help free peoples to maintain their free institutions and their national integrity against aggressive movements that seek to impose upon them totalitarian regimes.” He asked Congress for $400 million to defend Greece and Turkey from Soviet aggression. Congress approved the request in May 1947, signalling a departure from the former policy of non involvement in European affairs.
Truman’s Speech overturned the Monroe Doctrine and led directly to the Marshall Plan. It set a precedent for the principle of ‘collective security’ – building up a network of allies and friendly states to which the US gave military aid free of charge – and NATO.
In America, it whipped up the ‘Red Scare’ of the 1950s and In Russia, it convinced the Soviets that America was indeed attacking Soviet Communism.
The Truman Doctrine included the policy of containment, as Clark Clifford said in 1972: ‘we were concerned about preventing Soviet control of larger areas of the world than they already controlled’.
“‘We hope that in years ahead more and more nations will come to know the advantages of freedom and liberty” President Truman, May 15 1947
St. Rosemary Educational Institution. "Truman Doctrine: Historical Significance." http://schoolworkhelper.net/. St. Rosemary Educational Institution, Last Update: 2015. Web. Retrieved on: Tuesday 24th November 2015. http://schoolworkhelper.net/truman-doctrine-historical-significance/.