Nuclear weapon
Since the atomic bombings of Hiroshima and Nagasaki, nuclear weapons have been detonated over two thousand times for testing and demonstration. Only a few nations possess such weapons or are suspected of seeking them. The only countries known to have detonated nuclear weapons—and acknowledge possessing them—are (chronologically by date of first test) the United States, the Soviet Union (succeeded as a nuclear power by Russia), the United Kingdom, France, China, India, Pakistan, and North Korea. Israel is believed to possess nuclear weapons, though, in a policy of deliberate ambiguity, it does not acknowledge having them. Germany, Italy, Turkey, Belgium and the Netherlands are nuclear weapons sharing states. South Africa is the only country to have independently developed and then renounced and dismantled its nuclear weapons.
Treaty on the Non-Proliferation of Nuclear Weapons
Israel has a long-standing policy of deliberate ambiguity with regards to its nuclear program (see List of countries with nuclear weapons). Israel has been developing nuclear technology at its Dimona site in the Negev since 1958, and some nonproliferation analysts estimate that Israel may have stockpiled between 100 and 200 warheads using reprocessed plutonium. The position on the NPT is explained in terms of "Israeli exceptionality", a term coined by Professor Gerald M. Steinberg, in reference to the perception that the country's small size, overall vulnerability, as well as the history of deep hostility and large-scale attacks by neighboring states, require a deterrent capability.