Chapter 1 Nuclear Disarmament (1) Status of Nuclear Forces (estimates)
(1) Status of Nuclear Forces (estimates)
As of December 2019, eight countries have declared that they have nuclear weapons. According to Article IX-3 of the Nuclear Non-Proliferation Treaty (NPT), “a nuclear-weapon State is one which has manufactured and exploded a nuclear weapon or other nuclear explosive device prior to 1 January 1967.” China, France, Russia, the United Kingdom, and the United States meet this requirement, and have acceded to the NPT as nuclear-weapon states (NWS) as defined by the treaty. The three other countries that have tested nuclear weapons and declared having them are India, Pakistan and North Korea. India and Pakistan have never been parties to the NPT. Israel, a non-NPT state, has maintained a policy of “nuclear ambiguity” by neither confirming nor denying having nuclear weapons, although it is widely considered that it has them. (No conclusive evidence has emerged that Israel has conducted a nuclear explosive test.) In 2003, North Korea declared withdrawal from the NPT, and acquisition of nuclear weapons. In this report, these four additional states that have publicly declared or are believed to possess nuclear weapons are referred to as “other nuclear-armed states.”
The number of nuclear weapons, which grew to approximately 70,000 at the peak of the Cold War era, has been reduced significantly since the late 1980s. According to the estimates produced by the Stockholm International Peace Research Institute (SIPRI), however, an estimated 13,865 nuclear weapons still exist on the earth, and the U.S. and Russian nuclear stockpiles together constitute more than 90 percent of the total.2 Compared to the approximately 8,700 nuclear weapons that were eliminated between 2010 and 2019, the 600 nuclear weapons eliminated between 2018 and 2019 indicates that the pace of reduction has been slowing. It is widely estimated that China, India and Pakistan have each added about 10 warheads annually for the past several years (see Tables 1-1 and 1-2).
Among nuclear-armed states, France declared it possesses 300 nuclear weapons,3 and the United Kingdom announced plans to reduce its total nuclear stockpiles to not more than 180 by the mid-2020s. Other countries have not declassified the exact number of nuclear weapons in their arsenal.4Meanwhile, the United States has recently declassified information more actively. However, the Department of Defense decided not to disclose the information regarding the current number of possessed nuclear weapons as requested by a U.S. think tank in 2019.5
2 Stockholm International Peace Research Institute, SIPRI Yearbook 2019: Armaments, Disarmament and International Security (Oxford: Oxford University Press, 2019), chapter 6.
3 In addition, France reports that “[I]t has no undeployed weapons. All of its weapons are deployed and operational.” NPT/CONF.2015/10, March 12, 2015.
4 On this point, Bruno Tertrais explains the reasons as following: “Stockpiles include weapons which are not entirely functional (when exactly does an atomic device become a ‘nuclear weapon’?), or which are used for nondestructive testing. As a result, giving an exact number can be difficult, misleading, and/or beaccurate just for a given day.” Bruno Tertrais, “Comments on Hiroshima Report of March 2013,” Hiroshima Report Blog: Nuclear Disarmament, Nonproliferation and Nuclear Security, October 29, 2013, http://hiroshima- report.blogspot.jp/2013/10/op-ed-bruno-tertrais-comments-on.html.
5 Hans M. Kristensen, “Pentagon Slams Door on Nuclear Weapons Stockpile Transparency,” Federation of American Scientists, April 17, 2019, https://fas.org/blogs/security/2019/04/stockpilenumbersecret/.