How did world war 2 end and the cold war begin?

WW2 ended in Germany when the Allied forces completely surrounded Germany. WW2 ended in the Pacific when the U.S dropped the nuke on Japan. This ended WW2, but since Russia saw this they want to make their own nukes. The U.S saw that and feared an attack from communism so they made more nukes, This created massive tensions between the two countries. This started the Cold War.

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