Nuclear proliferation

Nuclear proliferation is the spread of <a href="/facts/Nuclear_weapons/QVdBcMdm">nuclear weapons</a>, fissile material, and weapons-applicable nuclear technology and information to nations not recognized as "<a href="/facts/List_of_states_with_nuclear_weapons/urhNKh4Q">Nuclear Weapon States</a>" by the <a href="/facts/Treaty_on_the_Non-Proliferation_of_Nuclear_Weapons/yE0ekVtm">Treaty on the Non-Proliferation of Nuclear Weapons</a>, 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 <a href="/facts/Nuclear_warfare/HLRLRh4F">nuclear warfare</a> (up to and including the so-called <a href="/facts/Countervalue/uIvfHqr5">countervalue</a> targeting of civilians with nuclear weapons), de-stabilize international or regional relations, or infringe upon the national sovereignty of <a href="/facts/Nation_state/1T5FVEJP">nation states</a>.
Four countries besides the five recognized Nuclear Weapon States have acquired, or are presumed to have acquired, nuclear weapons: <a href="/facts/India/1kKHcnxM">India</a>, <a href="/facts/Pakistan/cbIsvJy1">Pakistan</a>, <a href="/facts/North_Korea/Q41laakP">North Korea</a>, and <a href="/facts/Israel/dEe3IcaY">Israel</a>. None of these four are a party to the NPT, although North Korea acceded to the NPT in 1985, then withdrew in 2003 and conducted its first <a href="/facts/List_of_nuclear_weapons_tests_of_North_Korea/JMDoHEL3">nuclear test</a> in 2006. One critique of the NPT is that the treaty is discriminatory in the sense that only those countries that tested nuclear weapons before 1968 are recognized as nuclear weapon states while all other states are treated as non-nuclear-weapon states who can only join the treaty if they forswear nuclear weapons.
Research into the development of nuclear weapons was initially undertaken during World War II by the United States (in cooperation with the United Kingdom and Canada), Germany, Japan, and the USSR. The United States was the first and is the only country to have used a nuclear weapon in war, when it used <a href="/facts/Atomic_bombings_of_Hiroshima_and_Nagasaki/fRpj8aJA">two bombs against Japan</a> in August 1945. After surrendering to end the war, Germany and Japan ceased to be involved in any nuclear weapon research. In August 1949, the <a href="/facts/RDS-1/mgXDp8fa">USSR tested a nuclear weapon</a>, becoming the second country to detonate a nuclear bomb. The <a href="/facts/Nuclear_weapons_and_the_United_Kingdom/lK8jPFP1">United Kingdom first tested a nuclear weapon</a> in October 1952. <a href="/facts/France_and_weapons_of_mass_destruction/RGpsjtUa">France first tested a nuclear weapon</a> in 1960. The <a href="/facts/China_and_weapons_of_mass_destruction/SeQ2B1CW">People's Republic of China detonated a nuclear weapon</a> in 1964. India conducted its <a href="/facts/India_and_weapons_of_mass_destruction/IcG8vgjd">first nuclear test</a> in 1974, which prompted Pakistan to develop its <a href="/facts/Pakistan_and_weapons_of_mass_destruction/sfNPnK3S">own nuclear program</a> and, when India conducted a second series of nuclear tests in 1998, Pakistan followed with a series of tests of its own. In 2006, North Korea conducted its <a href="/facts/2006_North_Korean_nuclear_test/eartLjgg">first nuclear test</a>.

Nuclear proliferation open-in-new

Nuclear proliferation