Nuclear weapons debate
After the bombings of Hiroshima and Nagasaki, the world’s nuclear weapons stockpiles grew, and nuclear weapons have been detonated on over two thousand occasions for testing and demonstration purposes. Countries known to have detonated nuclear weapons—and that acknowledge possessing such weapons—are (chronologically): the United States, the Soviet Union (succeeded as a nuclear power by Russia), the United Kingdom, France, the People's Republic of China, India, Pakistan, and North Korea.
2010 NPT Review Conference
The Nuclear Nonproliferation Treaty (NPT), which entered into force in 1970, recognizes five countries as nuclear-weapon states (the United States, Russia, the United Kingdom, France, and China), who commit to pursue disarmament, and the right of other signatories to use nuclear technology for peaceful purposes, conditional upon their non-acquisition of nuclear weapons. Its ratification is nearly universal because it is adhered by 189 states, including five nuclear-weapon states, with the exception of Israel, India, and Pakistan. North Korea left the NPT and tested its first nuclear weapon in 2006.