Simple:
First, the U.S. dropped the two nuclear bomb shells at two separate Japanese cities (Hiroshima and Nagasaki) to show the entire world that U.S.A. will never be DEFEATED. Not even the Japanese Empire can stop the U.S. from becoming the new world leader! The United States is the champion of DEMOCRACY, FREEDOM, LIBERTY, EQUALITY, JUSTICE, and MAN'S PURSUIT OF HAPPINESS.
Then, the creation of The Berlin Wall in Germany that splits East and West. The creation of European Union, and the recognition of the state of the Soviet Union.
Most common citizens from Germany, Russia, USSR, Ukraine, Poland, Italy, Greece, Portugal, Spain, Czechoslovakia, Hungary, Austria, the rest of Europe, and other Asian countries like Japan and South Korea DEFECTED to the West by seeking asylum, marrying American wives, and leaving their homeland for the sake of the United States's global domination...