Some of Truman's decisions like fighting against communism by manking the Truman Dcotrine and laying an anti-communism bedrock for foreign policy, trying to stop the expansion of the USSR and Manipulating Russian repartitions from World War II contributed to the start of the Cold War.
it is also important to note that even though Truman contribute to the start of the cold war, To a large extent, Stalin's actions were also responsible for the onset of the Cold War. Stalin displayed a lack of trustworthiness, evident in the Yalta conference during February 1945, and spread communism into eastern European states. This led to mutual distrust between the USSR and the United States.
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