Answer:
War crimes trials:
The Nuremberg trials were a series of military tribunals held after World War II by the Allied forces under international law and the laws of war.
How the division helped the Allies:
The West wanted to revive the German economy and combine the three western zones into one area. Soviet Union feared this union because it gave the one combined zone more power than its zone. ... After Germany was divided into two parts, East Germany built the Berlin Wall to prevent its citizens from fleeing to the west. (essentially, they wanted to maintain control over Germany and not leave it to the Soviets to take over and gain power).
Atom bomb and international relations:
In August 1945 the USA detonated two atomic bombs over the Japanese cities of Hiroshima and Nagasaki. The intention was to force Japan to surrender, thus avoiding a long war in the Pacific. This action had the added potential of pressurizing the USSR into negotiating over Eastern Europe and Germany.
Overall, the atomic bomb failed to allow the Americans to achieve their foreign policy goals of containment. In fact, the advent of the atomic bomb has probably encouraged Stalin to run risks, rather than deter him from doing so. The plan to use the atom bomb as leverage in foreign policy had failed.
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