North Korea nuclear crisis

Democratic People's Republic of Korea
First nuclear weapon test	9 October 2006
Last nuclear test	9 September 2016
Largest yield test	10 (South Korean estimates) - 30 kt(Estimation from Jeffrey Lewis of the California-based Middlebury Institute of International Studies) Yield is always disputed, since North Korea government never announced the exact yield among other factors such as the depth of the test took place and soil condition in the test site.
Total tests	5
Current stockpile (usable and not)	15–22 nuclear weapons equivalents? (rough 2015 ISIS estimate)
Current strategic arsenal	10–16 nuclear weapons? (rough 2015 estimate)
Cumulative strategic arsenal in megatonnage	<0.5 (2011 ISIS estimate)
Maximum missile range	4,000 km (Hwasong-10)
NPT party	Not a member (North Korea withdrew in 2003).

North Korea and weapons of mass destruction concerns North Korea (officially the Democratic People's Republic of Korea or DPRK), which declared in 2009 that it had developed a nuclear weapon, and possessed a small stockpile of relatively simple nuclear weapons. North Korea may also have a chemical weapon and/or biological weapons capability. Since 2003, North Korea is no longer a party to the Treaty on the Non-Proliferation of Nuclear Weapons.

The nuclear program can be traced back to about 1962, when North Korea committed itself to what it called "all-fortressization", which was the beginning of the hyper-militarized North Korea of today. In 1963, North Korea asked the Soviet Union for help in developing nuclear weapons, but was refused. The Soviet Union agreed to help North Korea develop a peaceful nuclear energy program, including the training of nuclear scientists. Later, China, after its nuclear tests, similarly rejected North Korean requests for help with developing nuclear weapons.

Soviet specialists took part in the construction of the Yongbyon Nuclear Scientific Research Center and began construction of an IRT-2000 research reactor in 1963, which became operational in 1965 and was upgraded to 8 MW in 1974. In 1979 North Korea indigenously began to build in Yongbyon a second research reactor, an ore processing plant and a fuel rod fabrication plant.

North Korea's nuclear weapons program dates back to the 1980s. Focusing on practical uses of nuclear energy and the completion of a nuclear weapon development system, North Korea began to operate facilities for uranium fabrication and conversion, and conducted high-explosive detonation tests. In 1985 North Korea ratified the NPT, but did not conclude the required safeguards agreement with the IAEA until 1992. In early 1993, while verifying North Korea's initial declaration, the IAEA concluded that there was strong evidence this declaration was incomplete. When North Korea refused the requested special inspection, the IAEA reported its non-compliance to the UN Security Council. In 1993, North Korea announced its withdrawal from the NPT, but suspended that withdrawal before it took effect.

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