Answer:
All of these choices are correct.
Step-by-step explanation:
Stalin: Isolationism
The soviet union leader Joseph Stalin Putin was the General Secretary of the Communist Party which controlled the whole USSR which included several modern-day nations like Ukraine, Russia, Afghanistan, and many more nations. Well, it was Stalin who was the leader of the Soviet Union during the cold war and his policy of isolationism was influenced by his beliefs in the communism theory.
Truman: containment
After World War II, the world was in turmoil and many countries were experiencing political upheaval. The US government, already fearful of communism as a result of George Kennan's Long Telegram, was shocked when a number of countries in Europe and Asia adopted communist governments in the late 1940s.
When the UK informed the US that it could no longer afford to fight the communist insurgencies in Greece and Turkey, US President Harry S. Truman issued what became known as the Truman Doctrine: a pledge that the US would do whatever was necessary, as economically, as well as militarily, to prevent the spread of communism throughout the world.
Chruchill: Buffer Zone
Winston Churchill declared in March 1946 that "an iron curtain has descended across Europe". On one side stood the communist bloc and on the other the non-communist nations.
The fate of Eastern Europe was one source of contention between the United States and the Soviet Union. The US was committed to free and democratic elections in Eastern Europe, while the Soviet Union wanted an Eastern European buffer zone to protect it from future Western attacks.
The Soviet Union annexed the Baltic states of Estonia, Latvia, and Lithuania, as well as parts of Czechoslovakia, Finland, Poland, and Romania, before the end of World War II. Albania formed a communist government in 1944 and Yugoslavia in 1945.