The successful attempt to put the satellite Sputnik into space confirmed the fear of the US citizens that the Soviet Union was capable of potentially placing weapons into space (like missile-technology satellites, etc).
The explosion of the Soviet atomic bomb on August 29, 1949, confirmed American fears about the Soviet Union by demonstrating that they possessed nuclear capabilities. This event intensified Cold War tensions, leading to changes in U.S. foreign policy and military strategies. The atmosphere of fear was compounded by other global events, such as the communist victory in China and the Korean War.
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