- Soviet Union:
- 1945 - The Soviet Union tests its first atomic bomb.
- 1957 - The Soviet Union successfully launches Sputnik 1, the first artificial satellite to orbit the earth.
- 1961 - Soviet cosmonaut Yuri Gagarin becomes the first person to travel into space.
- 1969 - The Soviet Union launches the Soyuz 4 mission, which resulted in the first human linkage in space.
- United States:
- 1942 - The United States conducts the Manhattan Project, which resulted in the development of the atomic bomb.
- 1945 - The United States releases the atomic bombs on Hiroshima and Nagasaki.
- 1947 - The Truman Doctrine is enacted, providing foreign aid to countries threatened by communism.
- 1961 - President Kennedy commits the United States to sending humans to the moon by the end of the decade.
- Space Race:
The Cold War era was marked by a competitive race in space between the United States and the Soviet Union. This competition led to numerous advancements in rocketry, space exploration, and astronomy.
- Nuclear Deterrence:
The development of atomic and hydrogen weapons in the Cold War brought about the establishment of the concept of nuclear deterrence. This doctrine aimed to maintain peace by preventing direct military conflict between the U.S. and the U.S.S.R. through the threat of mutually assured destruction.