IIN 1945, HAVING WON THE WAR, the Allies faced the challenge of creating a lasting peace. Cooperation, however, proved difficult to sustain. Motivated by different goals and hounded by misunderstandings, Great Britain and the United States on one side found themselves at loggerheads with the Soviet Union (U.S.S.R.). By 1949, most of Europe was divided into East and West Blocs allied with the U.S.S.R. and the United States, respectively. For the next forty years, the competing superpowers engaged in the Cold War, a determined competition for political and military superiority around the world.