Question

Why did the USA and the USSR put aside their differences temporarily in WWII?

Answer 1

WWII set the stage for the Cold War between America and the Soviet Union in several ways.  One way was the Soviet occupation of Eastern Europe.  At Yalta, Roosevelt only talked about free elections for Poland, but he did not give a timetable for this, with the idea that getting Soviet help to fight the Japanese later in the summer was the main objective.  Roosevelt died before he could negotiate with Stalin, so Eastern Europe would remain occupied for the next forty years with Soviet puppet regimes.  Another piece of distrust was the manner with which America dropped the atomic bomb.  When Roosevelt died, Soviet leadership probably knew more about the American nuclear program than Harry Truman did due to their spying.  Stalin expected to be kept informed on the program, but Truman only alluded to it whenever he talked to Soviet Foreign Minister Molotov.  America and the Soviet Union shared the occupation duties of Germany after the war, but the Soviet Union did not get a chance to occupy Japan, much to Stalin's anger.  

What was more important than the diplomatic frostiness between America and the Soviet Union was the disparity of strength between the two powers.  WWII bled the Soviet Union considerably more than any other nation.  Stalin accused the Allies of being slow to open a second European front in the war in order to further weaken the Soviet Union.  After the war America had the strongest navy, air force, and army in the world, and had an atomic bomb also.  Stalin had to show strength in order not to be perceived as weak to his Politburo back home and to hopefully scare the West into not going to war with the Soviet Union.  


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