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.
Global issue
Nuclear proliferation is the spread of nuclear weapons, fissionable material, and weapons-applicable nuclear technology and information to nations not recognized as "Nuclear Weapon States" by the Treaty on the Non-Proliferation of Nuclear Weapons (NPT), commonly known as the Non-Proliferation Treaty or NPT. Proliferation has been opposed by many nations with and without nuclear weapons, as governments fear that more countries with nuclear weapons will increase the possibility of nuclear warfare (up to and including the so-called "countervalue" targeting of civilians with nuclear weapons), de-stabilize international or regional relations, or infringe upon the national sovereignty of states.