In 1945, Oppenheimer and his team successfully detonated a nuclear weapon in New Mexico, USA. Over the next half-century, nations large and small vied to possess this weapon of death. For rulers, nuclear weapons are a means of intimidation, but for the common people, after witnessing the apocalyptic scenes of Hiroshima and Nagasaki, the radioactive fallout from national nuclear tests became a greater concern. Thus, in 1963, the United States, the United Kingdom, and the Soviet Union signed the Partial Test Ban Treaty (PTBT) in Moscow, banning all nuclear tests except underground ones, moving nuclear testing out of the public eye and underground.

Although the PTBT prohibited non-underground nuclear tests, it wasn't until the 1980s that all nuclear-armed nations (except North Korea) were willing to comply with the norms. Since 1945, countries have conducted over 2,000 nuclear tests, with the most conducted by the United States, the Soviet Union, France, the United Kingdom, China, India, Pakistan, and North Korea. Operationally, nuclear tests are actually to test the effectiveness of bombs or warhead devices, the energy released by explosions, and to collect data for research purposes.