Editing Nuclear weapons testing (section)

{{Short description|Controlled detonation of nuclear weapons for scientific or political purposes}}
[[File:Castle Bravo nuclear test (cropped).jpg|thumb|The [[mushroom cloud]] from the [[Castle Bravo]] [[thermonuclear weapon]] test in 1954, the largest nuclear weapons test ever conducted by the United States]]
{{Nuclear weapons}}
{{Weapons of mass destruction}}
'''Nuclear weapons tests''' are experiments carried out to determine the performance of [[nuclear weapon]]s and the effects of [[Nuclear explosion|their explosion]]. Nuclear testing is a sensitive political issue. Governments have often performed tests to signal strength. Because of their destruction and [[fallout]], testing has seen opposition by civilians as well as governments, with international bans having been agreed on. Thousands of tests have been performed, with most in the second half of the 20th century.

The first nuclear device was detonated as a test by the United States at the [[Trinity site]] in [[New Mexico]] on July 16, 1945, with a yield approximately [[TNT equivalent|equivalent]] to 20 [[kiloton]]s of [[TNT]]. The first [[thermonuclear weapon]] technology test of an engineered device, codenamed [[Ivy Mike]], was tested at the [[Enewetak Atoll]] in the [[Marshall Islands]] on November 1, 1952 (local date), also by the United States. The largest nuclear weapon ever tested was the [[Tsar Bomba]] of the [[Soviet Union]] at [[Novaya Zemlya]] on October 30, 1961, with the largest yield ever seen, an estimated 50–58 [[TNT equivalent|megatons]].

With the advent of nuclear technology and its increasingly global fallout an [[anti-nuclear movement]] formed and in 1963, three (UK, US, Soviet Union) of the then four nuclear states and many non-nuclear states signed the [[Limited Test Ban Treaty]], pledging to refrain from testing nuclear weapons in the atmosphere, underwater, or in [[outer space]]. The treaty permitted [[underground nuclear testing]]. [[France and weapons of mass destruction|France]] continued atmospheric testing until 1974, and [[China and weapons of mass destruction|China]] continued until 1980. Neither has signed the treaty.<ref>"The Treaty has not been signed by France or by the People's Republic of China." US Department of State, [https://2009-2017.state.gov/t/isn/4797.htm Limited Test Ban Treaty].</ref>

Underground tests conducted by the Soviet Union continued until 1990, the United Kingdom until 1991, the United States until 1992, and both China and France until 1996. In signing the [[Comprehensive Nuclear-Test-Ban Treaty]] in 1996, these countries pledged to discontinue all nuclear testing; the treaty has not yet entered into force because of its failure to be ratified by eight countries. Non-signatories [[India and weapons of mass destruction|India]] and [[Pakistan and weapons of mass destruction|Pakistan]] last tested nuclear weapons in 1998. [[North Korea]] conducted [[List of nuclear weapons tests of North Korea|nuclear tests]] in [[2006 North Korean nuclear test|2006]], [[2009 North Korean nuclear test|2009]], [[2013 North Korean nuclear test|2013]], [[January 2016 North Korean nuclear test|January 2016]], [[September 2016 North Korean nuclear test|September 2016]] and 2017. The [[2017 North Korean nuclear test|most recent confirmed nuclear test]] {{As of|2017|9|alt=occurred}} in September 2017 in North Korea.