Nuclear-weapons design and testing

Abstract

China's nuclear arsenal has long been an enigma. It is a small force, based almost exclusively on land-based ballistic missiles, maintained at a low level of alert and married to a no-first-use doctrine – all choices that would seem to invite attack in a crisis. Chinese leaders, when they have spoken about nuclear weapons, have articulated ideas that sound odd to the Western ear. Mao Zedong's oft-quoted remark that ‘nuclear weapons are a paper tiger’ seems to be bluster or madness. China's nuclear forces are now too important to remain a mystery. Yet Westerners continue to disagree about basic factual information concerning one of the world's most important nuclear-weapons states. This Adelphi book documents and explains the evolution of China's nuclear forces in terms of historical, bureaucratic and ideological factors. There is a strategic logic at work, but that logic is mediated through politics, bureaucracy and ideology. The simplest explanation is that Chinese leaders, taken as a whole, have tended to place relatively little emphasis on the sort of technical details that dominated US discussions regarding deterrence. Such profound differences in thinking about nuclear weapons could lead to catastrophic misunderstanding in the event of a military crisis between Beijing and Washington.

Notes

1 For a primer on China's warhead handling system, see Mark Stokes, ‘China's Nuclear Warhead Storage and Handling System’, Project 2049 Institute, 12 March 2010, http://www.project2049.net/documents/chinas_nuclear_warhead_storage_and_handling_system.pdf.

2 The US appears to believe that the DF-3 and DF-4 use the same warhead, while the DF-5 uses a different warhead.

3 Lars-Erik De Geer, ‘The radioactive signature of the hydrogen bomb’, Science & Global Security, vol. 2, 1991, pp. 351–63.

4 The IAEA defines a significant quantity of plutonium as 8kg, which is sufficient for a simple fission device of the sort that a state might manufacture as a first weapon and includes an allowance for the loss of plutonium during processing. ‘Fat Man’, the device exploded in Nagaski in 1945, contained about 6kg of plutonium.

5 Ibid.

6 See Ian Hoffman and Dan Stober, A Convenient Spy: Wen Ho Lee and the Politics of Nuclear Espionage (New York: Simon & Schuster, 2002), p. 109.

7 CIA, ‘The Chances of an Imminent Communist Chinese Nuclear Explosion’, Special National Intelligence Estimate, 26 August 1964, approved for release May 2004.

8 For an initial chronology of China's nuclear tests, see Thomas Reed and Danny Stillman, ‘The Chinese Nuclear Tests, 1964–1996’, Physics Today, September 2008.

9 China Today: Defense Science and Technology, Volume 1 (Beijing: National Defense Industry Press, 1993) p. 232.

10 Ultimately the US conducted a single test of a W47 nuclear weapon on a Polaris missile, fired at reduced range to the Pacific test site in May 1962. The US Navy provides a description of the event, available at http://www.navy.mil/navydata/cno/n87/usw/issue_24/frigate_bird2.htm.

11 China Today: Defense Science and Technology, pp. 229–30

12 An account in Xinhua in 2009 describes that ‘imperialist powers’ viewed China's nuclear programme as ‘a bullet without a gun’ because China did not have a means of delivery at the time of initial nuclear tests. See ‘DF-2A Missile Reversed New China's Bullet Without a Gun Situation’, Xinhua, 3 April 2009, http://www.qh.xinhuanet.com/misc/2009-04/03/content_16147706.htm.

13 China Today: Defense Science and Technology, pp. 226-228.

14 One technical feature of the design is the use of a uranium deuteride initiator. Western experts were puzzled by a photograph of Pakistani scientist A.Q. Khan in front of a blackboard with a diagram of a nuclear weapon that included the phrase ‘urandeuteride initiator’. As it turns out, four scientists from the Southwest Institute of Fluid Mechanics in Sichuan published a detailed explanation in a 1989 paper entitled ‘Fusion Produced by Implosion of Spherical Explosive’. The paper is included in the proceedings of an American Physical Society meeting published as Shock Compression of Condensed Matter, S.C. Schmidt, James N. Johnson, Lee W. Davison (eds), (North-Holland, 1990). See also Jeffrey Lewis, ‘Uranium Deuteride Initiators’, Arms Control Wonk, 14 December 2009, http://lewis.armscontrolwonk.com/archive/2567/uranium-deuteride-initiators.

15 De Geer, ‘The radioactive signature of the hydrogen bomb’. A ‘layer cake’ design is one where fusion occurs from spheres of thermonuclear fuel surrounding the fission core, rather than a ‘true’ thermonuclear device involving radiation implosion of a physically separate secondary. Sloika is usually translated as layer cake.

16 China Today: Defense Science and Technology, p. 249.

17 China may have intended to use the bombers for operations in addition to testing: ‘In September 1967 the government assigned the task for retrofitting the H-5 into a nuclear carrier which could be used both for nuclear test and operational missions’; see China Today: Aviation Industry (Beijing, China Aviation Industry Press, 1989) pp. 146–47.

18 China Today: Aviation Industry, pp. 144, 146 and 155.

19 Deng Jiaxian, Biographies of the Founders of the Nuclear, Missile, and Satellite Programme (Beijing: Tsinghua University Press, 2001).

20 For a first-person account of the failed 1979 test by a member of the crew sent to recover the remains of the device, see: http://blog.sina.com. cn/s/blog_71e4f47201018ah4.html.

21 Harold Feiveson, Christopher Paine and Frank von Hippel, ‘A Low Threshold Test Ban is Feasible’, Science, vol. 238, no. 4826, 23 October 1987, p. 458.

22 China Today: Defense Science and Technology, pp. 196–97.

23 For a thorough review of early US thermonuclear development and testing, see Chuck Hansen, Swords of Armageddon: U.S. Nuclear Weapons Development since 1945, October 1995, Volume III. (1995).

24 Xu J. Niao, Kan di qiu - zhong guo zhan lue dao dan zhen di gong cheng ji shi (Beijing: PLA Literature and Art Publishing House, 2006), p. 361.

25 Deng, Biographies, pp. 55–63.

26 John Lewis and Xue Litai, China Builds the Bomb, (Stanford University Press, 1988) pp. 155–160; and Lewis and Xue, China's Strategic Seapower: The Politics of Force Modernization in the Nuclear Age (Stanford University Press, 1996) pp. 177–78.

27 Lewis and Xue, China's Strategic Seapower, pp. 177–78.

28 China's first scientific publication on pulse-neutron tubes dates to 1977. See Huanfa Zhongzi Ce Jing Xiezuo Zu, ‘Huanfa Zhongzi Ce Jing’, Yuanzineng Kexue Jishu, February 1977.

29 De Geer, ‘The radioactive signature of the hydrogen bomb’.

30 Lars-Erik De Geer, ‘Chinese Atmospheric Nuclear Explosions from a Swedish Horizon: A Summary of Swedish Observations of Chinese Nuclear Test Explosions in the Atmosphere, 1964–1980’, paper prepared for the Scope-Radtest Workshop in Beijing, 19–21 October 1996.

31 The average amount of plutonium in the US stockpile can be obtained by dividing the stockpile of plutonium (46.8 metric tonnes) by the size of the warhead stockpile at the time (approximately 11,100 warheads), giving a result of about 4kg per warhead. See Jeffrey Lewis, ‘Grading the NPR on Transparency’, Arms Control Wonk, 13 April 2010, http://lewis.armscontrolwonk. c o m / a r c h i v e / 2 6 8 7 / grading-the-npr-transparency.

32 Thomas Cochran and Christopher Paine, ‘The Amount of Plutonium and Highly-Enriched Uranium Needed for Pure Fission Nuclear Weapons’, Natural Resources Defense Council, 13 April 1995, http://www.nrdc.org/nuclear/fissionw/fissionweapons.pdf.

33 This section draws heavily on research conducted with Jonathan Ray for his master's thesis. A more complete account can be found in his forthcoming monograph, Jonathan Ray, Red China's Capitalist Bomb: Inside the PRC's Neutron Bomb Program, (China Strategic Perspectives, National Defense Univeristy, forthcoming 2014).

34 Walter Pincus, ‘Neutron Killer Warhead Buried in ERDA Budget’, Washington Post, 6 June 1977 and ‘Pentagon Pushes Neutron Shell for Artillery Forces’, Washington Post, 24 June 1977.

35 See FBIS, Document ID CHI-77-134, ‘Ta Kung Pao Discusses Neutron Bomb Issue’, from Hong Kong Ta Kung Pao, in Chinese, 9 July 1977, and ‘U.S. President Carter Asks Congress to Agree to Neutron Bomb Production’, People's Daily, 16 July 1977.

36 Mao Zedong died in September 1976 and the Cultural Revolution ended soon after. Yu Min's recollection is taken from Deng's Biographies, pp. 56–63. Yu says the order to develop a ‘second generation of nuclear weapons’ came in the mid-1970s. He also recalls a conversation with Qian Sanqiang, who had ‘come out of retirement’, returned to the China Academy of Sciences (CAS) and invited Yu Min to come to CAS. Yu declined the invitation to continue work on the ERW and miniaturisation programmes. Xue Bencheng said in an interview that China began researching ERWs in the 1970s. See FBIS, Document ID CHI-2001-0613, ‘PRC Chief Engineer of Neutron Bomb Interviewed on Nuclear Weapons Development’, from Chengdu Sichuan Ribao, in Chinese, 11 June 2001.

37 Poem by Zhang Aiping: ‘No Limits to What Can Be Climbed – On Reading Marshal Ye's Poem “Storm the Strategic Pass”’, People's Daily, 21 September 1977. Translation by Jonathan Ray.

38 ‘The Neutron Bomb’, People's Daily, 22 September 1977.

39 On 22 July 1977 the Communist Party officially restored Deng to the offices of vice premier of the State Council, vice chairman of the Central Committee, vice chairman of the Military Commission and chief of the General Staff of the PLA.

40 Chen Junxiang, China's Unique Path for Developing Nuclear Weapons: The Nuclear, Missile and Satellite Program (Jiuzhou Press, 2001), p. 157. Chen worked at the Ninth Academy and supported nuclear tests.

41 Deng, Biographies, pp. 56–63.

42 Liu Huaqing, A Review of the Neutron Bomb (China's Defense Science and Technology Information Centre, 1979.) A record of this publication is available at: http://218.249.41.17/was40/detail?record=57961&channelid=10234.

43 Liu Huaqiu, China and the Neutron Bomb (Stanford, CA: Stanford University Press, 1988).

44 ‘Stressing politics’ was part of the Communist Party vernacular from 1998 to the early 2000s. Jiang Zemin's ‘Three Stress Campaign’ emphasised the need for party members to study politics and adapt ideology to changing circumstances.

45 FBIS, ‘PRC Chief Engineer of Neutron Bomb Interviewed on Nuclear Weapons Development’.

46 Deng, Biographies, p. 58.

47 China Today; Defense Science and Technology, p. 223.

48 Chen, China's Unique Path for Developing Nuclear Weapons, pp. 160-161 and FBIS, ‘PRC Chief Engineer of Neutron Bomb Interviewed on Nuclear Weapons Development’.

49 Xie Guang, Dangdai, p. 274.

50 Ibid., p. 223.

51 Chen, China's Unique Path for Developing Nuclear Weapons, pp. 160–61.

52 Translation by Jonathan Ray. Poem appears in Yu Min, Biographies of the Founders of the Nuclear, Missile, and Satellite Program (Beijing: Tsinghua University Press, 2001), as well as in numerous news articles and biographies on Deng Jiaxian.

53 ‘Facts Speak Louder Than Words and Lies Will Collapse by Themselves – Further Refutation of the Cox Report’, People's Republic of China, Information Office of the State Council, 15 July 1999.

54 Min, Biographies, pp. 56–63.

55 For a history of the 863 programme, see Evan A. Feigenbaum, China's Techno-Warriors: National Security and Strategic Competition from the Nuclear to the Information Age (Stanford, CA: Stanford University Press, 2003), pp. 141–88.

56 An alternate possibility is that the yields lie at the low end of the range of uncertainty and that the tests represent a truncated development programme for the solid-fuelled missiles that gave way to the design tested from 1992 to 1996.

57 It is reported as a 400kt yield in Lewis and Xue, China's Strategic Seapower, p. 177, and as a 200– 300kt yield in Lewis and Hua, ‘China's Ballistic Missile Programs’, International Security, p. 30. Both are cited according to general design plans.

58 This clustering is a composite of multiple interpretations of the available seismic data, as described in Jeffrey Lewis, The Minimum Means of Reprisal, p. 92. See Aoife O'Mongain, Alan Douglas and John B. Young, ‘Body-wave Magnitudes and Locations of Presumed Explosions at the Chinese Test Site, 1967–1996’, 22nd Annual DoD/DoE Seismic Research Symposium: Planning for Verification of and Compliance with the Comprehensive Nuclear Test-Ban Treaty, New Orleans, LA, 15 September 2000; John R. Murphy, ‘Yield Estimation and Bias at the Chinese Lop Nor Test Site’, 14th Annual DARPA/PL Seismic Research Symposium, Tucson, Arizona, 18 September 1992; Xiaoping Yang, Robert North, Carl Romney and Paul G. Richards, ‘Worldwide Nuclear Explosions’, Colombia University, http://www.ldeo.columbia.edu/~richards/my_papers/WW_nuclear_tests_IASPEI_HB.pdf.

59 ‘Annual Report to Congress: Military and Security Developments Involving the People's Republic of China’, US Department of Defense, 2010, p. 2, http://www.defense.gov/pubs/pdfs/2010_cmpr_final.pdf.

60 Russian throw-weights are from START aggregate data.

61 Feiveson, Paine and von Hippel, ‘A Low Threshold Test Ban is Feasible’.

62 No title, NAIC-1442-0629-97, 10 December 1996, as reproduced in Bill Gertz, Betrayal (Washington, DC: Regnery, 2001), pp. 251–52.

63 Alex Wellerstein, ‘Kilotons per kilogram’, Restricted Data, 23 December 2013, http://blog. nuclearsecrecy.com/2013/12/23/ kilotons-per-kilogram/.

64 Office of Scientific and Weapons Research, Central Intelligence Agency, China's Nuclear Weapons Testing: Facing Prospects for a Comprehensive Ban, 30 September 1993, approved for release October 2003. Available at: http://www.foia.cia.gov/sites/default/files/document_conversions/89801/DOC_0000996367.pdf

65 Office of Scientific and Weapons Research, Central Intelligence Agency, China's Nuclear Weapons Testing: Facing Prospects for a Comprehensive Ban, 30 September 1993, approved for release October 2003. Available at: http://www.foia.cia.gov/sites/default/files/document_conversions/89801/DOC_0000996367.pdf; ‘China Seeking Foreign Assistance To Address Concerns About Nuclear Stockpile Under CTBT’, Proliferation Digest, 29 March 1996, p. 38. Available at: http://www.foia.cia.gov/sites/default/files/document_conversions/89801/DOC_0000996348.pdf

66 Senior Chinese official, ‘The Modernization of Nuclear Weapon’, 3rd Meeting of Sino-American Strategic Nuclear Relations and Strategic Bilateral Conference, 9–10 June 2008, Beijing.

67 For example, satellite images show the road leading to the site was recently resurfaced.

68 Jeffrey Lewis, ‘Subcritical Testing at Lop Nor’, Arms Control Wonk, 3 April 2009, http://lewis.armscontrolwonk.com/archive/2239/subcritical-testing-at-lop-nor.

69 Classified systems are probably better. In the mid-1990s in the US it was down to hundreds. By the end of the decade the IMS was better, probably comparable, but AEDS is probably better, albeit not that far off. See: Jeffrey Lewis, ‘AFTAC’, Arms Control Wonk, 19 July 2011, http://lewis.armscontrolwonk. com/archive/4264/aftac. See also Ola Dahlam, Svein Mykkeltveit and Hein Haak, Nuclear Test Ban: Converting Political Visions to Reality (Stockholm: Springer, 2009).

70 Jeffrey Lewis, ‘AFTAC’, Arms Control Wonk, 19 July 2011, http://lewis.armscontrolwonk.com/archive/4264/aftac.

71 One estimate reports that ‘tests with yields on the order of 100 tons would not be detected seismically [at Lop Nor], even if there were no attempt at evasion [such as decoupling]’. From ’Possible Future Activities at China's Nuclear Test Site,’ Proliferation Digest, November 1996, p.23. Available at: http://www.foia.cia.gov/sites/default/files/document_conversions/89801/DOC_0000522904.pdf

72 A senior Chinese official has stated that China does not conduct so-called ‘hydronuclear’ tests that produce small amounts of yield that would evade detection. For current US estimates of monitoring capabilities, see National Research Council, The Comprehensive Nuclear Test Ban Treaty: Technical Issues for the United States (Washington DC: The National Academies Press, 2012).

73 US intelligence appears to have been primarily concerned with the computing power of the Galaxy-II computer. See ‘China: The Galaxy-II Computer and Nuclear-Related Research’, CIA, 3 August 1994, approved for release October 2003.

74 ‘China's Tianhe-2 Supercomputer Maintains Top Spot on 42nd TOP500 List’, Top500, http://www.top500.org/blog/lists/2013/11/press-release/.

75 De Geer, ‘The radioactive signature of the hydrogen bomb’.

76 Dan Stober and Ian Hoffman, A Convenient Spy: Wen Ho Lee and the Politics of Nuclear Espionage (New York: Simon & Schuster, 2007) p.233.

77 Ibid., p.234.

78 Ibid., 234

79 The Cox Report.

80 The concept of two-point implosion appeared in open literature as early as a 1956 drawing of a Swedish nuclear-weapons design that formed the basis of the Nth country experiment, in which two US graduate students designed a nuclear device based on open-source information.

81 David Wise, Tiger Trap: America's Secret Spy War with China (Boston: Houghton Mifflin Harcourt, 2011) pp. 50–58.

82 Harold Agnew, ‘Looking for Spies in the Nuclear Kitchen’, Letter to the editor, Wall Street Journal, 17 May 1999, p. A27, http://www.fas.org/irp/ops/ci/agnewwsj.html.

83 Ibid.