Answer:
Harry Truman, who succeeded Franklin Roosevelt, lacked trust in the Soviets. He made his suspicious quite evident, which increased hostilities during the Cold War.
Explanation:
With the end of World War II, Europe was destroyed and weakened politically and economically, with which emerged two world powers, the United States and the Soviet Union, which represented capitalism and socialism respectively.
When leaving the War, the Soviet Union aspired to extend the action of the socialism, starting in the east European. Noticing the expansion of socialism led by the Soviets, Britain's Winston Churchill began to motivate all capitalists to devise strategies to contain such an advance.
The US government declared support for this initiative, President Harry S. Truman, on March 12, 1947, addressed an aggressive address to the National Congress, pointing out all his lack of confidence in the Soviets and affirming that the countries capitalists should defend themselves against the socialist threat.
From this statement the Truman Doctrine was consolidated, and for some scholars the Cold War began, spreading a rivalry between capitalists and socialists.
