<P> The Iron Curtain was the name for the boundary dividing Europe into two separate areas from the end of World War II in 1945 until the end of the Cold War in 1991 . The term symbolizes the efforts by the Soviet Union to block itself and its satellite states from open contact with the West and its allied states . On the east side of the Iron Curtain were the countries that were connected to or influenced by the Soviet Union, while on the west side were the countries that were allied to the United States or nominally neutral . Separate international economic and military alliances were developed on each side of the Iron Curtain: </P> <Ul> <Li> Member countries of the Council for Mutual Economic Assistance and the Warsaw Pact, with the Soviet Union as the leading state </Li> <Li> Member countries of the North Atlantic Treaty Organization (NATO) and with the United States as the pre-eminent power </Li> </Ul>

Why did the soviet union build the iron curtain
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