What did the truman doctrine protect

Truman told Congress that "it must be the policy of the United States to support free people who are resisting attempted subjugation by armed minorities or by outside pressures."[2] Truman reasoned that because the totalitarian regimes coerced free peoples, they represented a threat to international peace and the national security of the United States. Truman made the plea amid the crisis of the Greek Civil War (1946–49). He argued that if Greece and Turkey did not receive the aid that they urgently needed, they would inevitably fall to communism with grave consequences throughout the region. Because Turkey and Greece were historic rivals, it was considered necessary to help both equally even though the threat to Greece was more immediate. Historian Eric Foner argues the Truman Doctrine "set a precedent for American assistance to anticommunist regimes throughout the world, no matter how undemocratic, and for the creation of a set of global military alliances directed against the Soviet Union."[3]
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The Truman doctrine was established in order to provide economic, military, and political help to any democratic nation in need of assistance.