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The Future of Japan’s Non-Nuclear Weapons Status

Published 30 Jul 2014

By William Larn

The debate over Japan’s non-nuclear weapons status is complex and continues to resurface during periods of regional instability. The technological superiority provided by Japan’s civilian nuclear energy programme and its stocks of weapons-grade fissile material mean Japan is capable of producing nuclear weapons.1 Although realism might suggest Japan will acquire nuclear weapons, it has thus far remained a non-nuclear weapons state. It is the intention of this essay to examine the likely near-future of Japan’s non-nuclear weapons status by assessing three key factors that influence Japan’s policy toward nuclear weapons: its national identity as a peaceful and non-nuclear weapons state, its commitment to the global non-proliferation regime, and its security calculations, focusing on the US-Japan alliance. The aim of this essay is to suggest that through these three factors, Japan will maintain its non-nuclear weapon status in the near-future.

Japan’s national identity as a peaceful and non-nuclear weapons state
Japan’s national identity as a non-nuclear weapons state and the only nation to have suffered the consequences of a nuclear weapons attack has led to its development as a highly pacifist state. In Japan, citizens continue to view activity connected to the military with extreme wariness. Commitment to the idea of a non-nuclear weapons state remains strong, even among the younger generation.2 Public opinion in Japan shows an aversion to nuclearisation.3 Polling conducted by the Asahi Shimbun newspaper in 1968, while China was testing nuclear weapons, found that only 21 per cent of the population favoured Japan acquiring nuclear weapons.4 In 1978 and 1981 numbers had fallen to between 15 and 16 per cent and by 1999, a poll taken by the National Institute for Research Advancement found that only 7 per cent of those polled would favour Japan acquiring nuclear weapons.5 These polls indicate a downward trend while Japan moves through periods of greater security. However, the nuclearisation debate resurfaces during periods of regional instability, challenging Japan’s anti-nuclear self- conception. For example, North Korea’s nuclear test in 2006 resulted in a fall in support for Japan remaining a non-nuclear weapons state, with the Yomiuri Shimbun newspaper reporting that 28.6 per cent of people polled agreed that there is sufficient reason to discuss whether or not Japan should possess nuclear weapons.6 The aftermath of North Korea’s actions caused conservative political leaders like former Foreign Ministers Nakagawa and Aso to suggest “chipping away at the nuclear taboo and [preparing a] national agenda for a fundamental re-examination of Japan’s security policy that includes consideration of the nuclear option”.7 The polls do not reflect mainstream anti-nuclear sentiment in Japan, but they do suggest that there is a need to discuss the nuclear option. This offers the chance for politicians to use public debate to shift Japan’s national identity. However, this will remain a difficult task, as after North Korea’s satellite launch in April 2009, 19.4 per cent of respondents supported Japan’s nuclearisation, but 72.8 per cent disagreed with it.8 These polls do, however, suggest that North Korea’s belligerent actions could push Japan to adopt a more hard-line defence policy. What remains influential in Japan maintaining a non-nuclear weapons status in the near-future is the almost universal antinuclear sentiment among the Japanese people.9 This suggests that the engrained national identity of Japan as a non-nuclear weapons state remains influential in maintaining this status.

Commitment to the global non-proliferation regime

Japan maintains a strong public commitment to the global non-proliferation regime and nuclear disarmament in an effort to “realize a peaceful and safe world free of nuclear weapons”.10 Japan remains a committed proponent of the Non-Proliferation Treaty (NPT) and the Comprehensive Test Ban Treaty (CTBT), and continues to be heavily engaged in their proceedings. Japan’s engagement is most evident through its involvement in submitting resolutions to the United Nations General Assembly’s (UNGA) First Committee each year and working papers to the NPT review conferences and preparatory committees on disarmament.11 Its commitment is evident in its opening remarks for the 2010 NPT Review Conference that states, “the threat [of ] nuclear weapons [are] among the most serious challenges that humankind faces… Japan has a moral responsibility to act at the forefront of efforts towards the elimination of nuclear weapons and is firmly committed to its Three Non-Nuclear Principles”: not possessing nuclear weapons, not producing them and not permitting their entry into the country.12 Moreover, Japan has intentions to “advance its nuclear disarmament diplomacy and further enhance the international regime for nuclear non-proliferation”.13 This is noticeable through the Non-Proliferation and Disarmament Initiative (NPDI) that sets out to encourage greater transparency surrounding nuclear disarmament.14 The NPDI submitted a working paper to the preparatory Committee for the 2015 NPT Review Conference that sets out the framework for NPT signatories to implement, in order to strengthen IAEA safeguards and promote a more effective non- proliferation regime.15 Japan maintains a multiple international obligations on this front, so if it seriously considered acquiring nuclear weapons it would have to remove itself from these international institutions; a “withdrawal from the NPT could damage the world’s most durable international non-proliferation regime.”16

Japan has also instituted domestic policy to safeguard its nuclear energy sector. The implementation of the Atomic Energy Basic Law of 1955 stipulates that “the research, development, and utilisation of atomic energy shall be limited to peaceful, purposes, aimed at ensuring safety and performed independently under democratic management, the results therefrom shall be made public to contribute to international cooperation.”17 Japan’s is committed to the International Atomic Energy Agency (IAEA), where its nuclear energy program accounts for 20-30 per cent of IAEA inspections activity.18 The Japanese military identify no value in acquiring nuclear weapons. Even without domestic restraints, military planners do not see a strategic logic in nuclearisation and refrain from implementing policy in the nuclear energy sector to convert any reactors for enrichment purposes.19 Consequently, Japan’s non-nuclear weapons status will remain influenced by its commitment to the international non-proliferation regime.

Security calculations – the US-Japan alliance

What elicits greater influence over Japan’s non- nuclear weapons status is the famous Article 9 of the Constitution, which stipulates “the Japanese people forever renounce war as a sovereign right of the nation and the threat or use of force as a means of settling international disputes.” Consequently, Japan has had to rely on security guarantees from other states, in particular the US. Thus it has been imperative that Japan “make ceaseless efforts to maintain and strengthen the deterrent capabilities of the Japan-US alliance for the peace and security of Japan.”20 US extended nuclear deterrence has played a vital role in influencing Japan’s non-nuclear weapons status, as Japanese nuclear possession would be contrary to US nuclear strategy.21 However, there has been advocacy in Japan to acquire nuclear weapons in order to pursue a foreign and defence policy that is strategically independent of the United States.22 Contrary to this, the bulk of Japanese leadership understands that national security would be poorly served by going nuclear.23 This is evident in the Japanese Defence Agency study conducted in 1995 that concluded a decision to go nuclear would only have a negative impact on Japan’s national security.24

While the US-Japan alliance remains strong, pro- nuclear advocates have suggested that “now that there is no longer any threat of Japan being drawn into the Communist camp, America has scant grounds to endanger itself in order to defend” Japan.25 This sentiment suggests that there is sufficient doubt that the US will defend Japan in an actual security crisis.26 However, this is not reflected on the international stage, as a joint statement issued by the Security Consultative Committee (SCC) reaffirmed the United States’ commitments “to the security of Japan through the full range of US military capabilities, including nuclear and conventional”.27 The SCC strategic vision is to revise the 1997 Guidelines for US-Japan Defense Cooperation through an expansion of the “security and defense cooperation in the Asia-Pacific region and beyond, and approving new measures that support the realignment of US forces in Japan.” 28 Moreover, the purpose of realignment is to “ensure that the US presence maintains deterrence and provides for the capabilities to defend Japan and respond to regional contingencies.”29 Following the SCC discussions, Secretary of State John Kerry reaffirmed that “The United States’ and Japan’s relationship has really long been the cornerstone of the regional peace and security of that region… we simply cannot achieve the goals that we want to achieve in that region and globally without ironclad guarantees between the United States and Japan.” Importantly Kerry highlighted that it was necessary “to update bilateral defense guidelines” that had not been altered since 1997 in an effort to bring closer security collaboration that would help the US and Japan to continue countering the threat from North Korea and maintain stability in the Asia-Pacific region.30 Lastly, the Japanese public has been concerned with regional security issues and is apprehensive of being abandoned by the US. This has led to renewed debates for Japan acquiring nuclear weapons, but it is evident that the US has no intention of reneging on its defensive agreements with Japan and as a result will continue to influence in a positive manner Japan’s current and near-future non-nuclear weapons status.


It appears likely that Japan will maintain its non-nuclear weapon status into the near future. Although conflict on the Korean Peninsula keeps Japan on edge, it is evident that through the combination of Japan’s national identity as a non-nuclear weapons state, its international and domestic commitments to the non-proliferation regime, and the continuing strength of the US-Japan alliance, Japan will maintain its non-nuclear weapons status in the near-future. Polling conducted in Japan since the inception of its non-nuclear policy indicates that there has been a decline in support for nuclearisation, though with periodic increases at times of regional insecurity. Though there remains overwhelming support to maintain Japan’s non-nuclear weapons status, Japan’s citizens feel the need to debate acquiring nuclear weapons. Japan has remained committed to promoting the non-proliferation regime through its membership of the NPT, CTBT and the IAEA, and makes considerable efforts to further the non-proliferation regime through its annual resolutions to the UNGA and working papers to the NPT. In order for Japan to remain a non-nuclear weapons state “the nuclear umbrella has been a necessary condition for Tokyo’s non-nuclear policy”.31 Japan has relied on the strength of the US-Japan alliance to guarantee its security in the Asia-Pacific region. Japan’s national identity as a peaceful and non-nuclear weapons state, its commitment to the global non-proliferation regime and its security calculations suggest that through these three factors, Japan will maintain its non-nuclear weapon status in the near-future.


William Larn is studying a Master of International Relations at the University of Melbourne after obtaining a Bachelor of Arts from Monash.




1 Hajime Izumi and Katsuhisa Furukawa, ‘Not Going Nuclear: Japan’s Response to North Korea’s Nuclear Test’, Arms Control Association (2007), accessed April 27, 2014,

2 Matake Kamiya, ‘Will Japan go nuclear? Myth and reality’, Asia-Pacfici Review, 2:2 (1995): pp. 5-19.

3 Llewelyn Hughes, ‘Why Japan Will Not Go Nuclear (Yet): International and Domestic Constraints on the Nuclearization of Japan’, International Secuirty, 31:4 (2007), pp. 67-96

4 Ibid, pp. 89

5 Ibid.

6 The Maureen and Mike Mansfield Foundation, ‘Yomiuri Shimbun Novemeber Opinion Polls,’ The Maureen and Mike Mansfield Foundation (2006), accessed 2April , 2014, polls/2006/poll-06-18.htm

7 Mike, M. Mochizuki, ‘Japan Tests the Nuclear Taboo’, The Nonproliferation Review, 14:2 (2007), pp. 304.

8 Reshmi Kazi, ‘Japan’s Nuclear Policy at Crossroads’, Strategic Analysis, 34:3 ( 2010), pp. 438

9 Matake Kamiya, ‘Will Japan go nuclear? Myth and reality’, pp. 8-9

10 Japan Atomic Energy Commission (AEC), Framework for Nuclear Energy Policy (Naka: AEC, 2005), pp. 14

11 Ministry of Foreign Affairs of Japan (MOFA), Facing Nuclear Dangers: An Action Plan For The 21st Century, (Tokyo: MOFA, 1999), accessed April 27, 2014, key.html

12 Tetsuro Fukuyama, 2010 Review Conference of the Parties To The Treaty on the Non-Proliferation of Nuclear Weapons, (Tokyo: MOFA, 2010), accessed April 27, 2014, state100504.html; Yoshihiko Noda, Message by Prime Minister of Japan to the Global Zero Summit, (Tokyo: MOFA, 2011), accessed April 27, 2014,

13 AEC, Framework for Nuclear Energy Policy, pp. 43

14 Department of Foreign Affairs and Trade (DFAT), Non-Proliferation and Disarmament Initiative (NPDI), (Canberra: DFAT), accessed Aril 27, 2014,

15 MOFA, Preparatory Committee for the 2015 Review Conference of the Parties to the Treaty on the Non-Proliferation of Nuclear Weapons, (Tokyo: MOFA, 2012), accessed April 27, 2014, event/2012/4/pdfs/0427_01_03.pdf; International Atomic Energy Agency (IAEA), IAEA Safeguards Overview: Comprehensive Safeguards Agreements and Additional Protocols, (Vienna: IAEA), accessed April 27, 2014,

16 Emma Chantlett-Avery and Mary Beth Nikitin, Japan’s Nuclear Future: Policy Debate, Prospects, and U.S. Interests, Congressional Research Service, February 19, 2009, pp. 1.

17 Government of Japan, Atomic Energy Basic Act (Act No. 186 of 1955), (Tokyo, Government of Japan, 2004), accessed April 27, 2014, http://www.

18 Mochizuki, ‘Japan Tests the Nuclear Taboo’.

19 Hughes, ‘Why Japan Will Not Go Nuclear (Yet): International and Domestic Constraints on the Nuclearization of Japan’.

20 Junnosuke Kishida, ‘Japan’s non-nuclear policy,’ Survival: Global Politics and Strategy, 15:1 (1973), pp. 15-20.

21 Sachio Nakato, ‘Japan’s Responses to the North Korean Nuclear Crisis: Responsive Engagement Perspectives,’ The Journal of East Asian Affairs, 27:1 (2013), pp. 47-74.

22 Mochizuki, ‘Japan Tests the Nuclear Taboo’.

23 Masaru Tomamoto, ‘The Emperor’s New Clothes: Can Japan Live Without the Bomb?’ World Policy Journal, 26:3 (2009), pp. 63-70.

24 Masako Toki, ‘Sixty Years After the Nuclear Devastation, Japan’s Role in the NPT,’ Nuclear Threat Initiative (Washington DC: 2005), accessed April 28, 2014, japan/

25 Mochizuki, ‘Japan Tests the Nuclear Taboo,’ pp. 313

26 Kazi, ‘Japan’s Nuclear Policy at Crossroads.’

27 Security Consultative Committee, Joint Statement of Japan-
U.S. Security Consultative Committee, (Washington D.C: 2013),
accessed April 28, 2014, texttrans/2013/10/20131003283979.html#axzz2zmWUc7SP

28 MOFA, The Guidelines For Japan-U.S. Defense Cooperation, (Tokyo: MOFA, 1997), accessed April 28, 2014, america/us/security/guideline2.html

29 Ibid

30 U.S. Department of State (USDOS), Remarks With Japanese
Foreign Minister Fumio Kishida After Their Meeting, (Washington D.C: USDOS, 2014), accessed April 28, 2014, remarks/2014/02/221459.htm

31 T.V Paul, ‘Aligned Major Economic Powers: Germany and Japan,’ in Power versus Prudence: Why Nations Forgo Nuclear Weapons, ed. T.V Paul (Montreal: McGill-Queen’s University Press, 2000), pp. 37-61.