Why might President Harry Truman have felt that the United States had been betrayed by the Soviet Union after World War II?

At the end of World War II, the United States expected the Soviet Union to allow countries in Eastern Europe that it had occupied to choose their own governments. Instead, the Soviets kept control and established communist governments friendly to Moscow. This made Truman feel that the Soviet Union had broken its promises and betrayed the wartime alliance. The correct choice is D, that the Soviet Union refused to give up control of conquered Eastern European lands.

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