Peace was not peaceful. The victors separated into two opposing camps. Berlin, divided into four sectors within the city but situated entirely in the Russian-controlled sector of Germany, became a pawn in the struggle between East and West. It was a time of the Truman Doctrine, the Marshall Plan, the Berlin Airlift, the North Atlantic Treaty Organization, the civil war in China, the retreat of the government of Nationalist China to Formosa, the inevitable explosion of an atomic bomb in the USSR.