Truman’s biggest concern was how Stalin might react to America’s development of an atomic bomb. Stalin simply shrugged his shoulders and took an attitude of “so what?”. One explanation is that Stalin knew more from his spies about the atomic bomb than Truman did. Another explanation is that Stalin had just acquired control of half of Germany and all of Eastern Europe and did not fear the United States in the slightest.{{fact}} | Truman’s biggest concern was how Stalin might react to America’s development of an atomic bomb. Stalin simply shrugged his shoulders and took an attitude of “so what?”. One explanation is that Stalin knew more from his spies about the atomic bomb than Truman did. Another explanation is that Stalin had just acquired control of half of Germany and all of Eastern Europe and did not fear the United States in the slightest.{{fact}} |