What were the facts about the Truman Doctrine

The united States had become increasingly alarmed at the rising power of the USSR and the spread of Communism in the countries behind the Iron Courtain.
Not content with their influence over the communist-dominated governments in the 'satellite Nations. of East Germany, Bulgaria, Hungary, Poland, Romania and Albania, The USSR sought to extend their power and communism to other countries in Eastern Europe and the Middle East. Tho of the Soviet's targets were Turkey and Greece.
The British were experiencing serious financial difficulties after WW2 and could not afford the expense of providing military aid.

In other words, maybe more simple.

The Truman Doctrine was a measure created by EE.UU that sought to support "free peoples who are resisting attempts at subjugation by armed minories or outside pressure".

The speech said: "I believe that we must help the peoples to forge their own destiny [...] Each nation must choose between two opposite ways of life [...] One rests on the will of the majority and characterized by its free institutions, by a representative government, by free elections, by the guarantee of the maintenance of individual liberties and by the absence of any political oppression [...] The other rests on the will of a minority imposed by the It has the strength of the majority, it relies on terror and oppression, it has a controlled press and radio, truncated elections and the suppression of personal liberties."