Nuclear warfare
After World War II, nuclear weapons were also developed by the Soviet Union (1949), the United Kingdom (1952), France (1960), and the People's Republic of China (1964), which contributed to the state of conflict and extreme tension that became known as the Cold War. In 1974, India, and in 1998, Pakistan, two countries that were openly hostile toward each other, developed nuclear weapons. Israel (1960s) and North Korea (2006) are also thought to have developed stocks of nuclear weapons, though it is not known how many. The Israeli government has never admitted or denied to having nuclear weapons, although it is known to have constructed the reactor and reprocessing plant necessary for building nuclear weapons. South Africa also manufactured several complete nuclear weapons in the 1980s, but subsequently became the first country to voluntarily destroy their domestically made weapons stocks and abandon further production (1990s). Nuclear weapons have been detonated on over 2,000 occasions for testing purposes and demonstrations.
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.