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Japan's Nuclear Ambitions

Below is an extract from the Citizens' Nuclear Information Center's submission to the Parliament of Australia's Joint Standing Committee on Treaties Inquiry into Nuclear Non-proliferation and Disarmament

Click here for a pdf version of the full submission, which was dated 16 January 2009.

1. Japan's Reprocessing and Uranium Enrichment Programs as a Proliferation Risk

As the victim of the atomic bombings of Hiroshima and Nagasaki, Japan is widely viewed as the last country that would consider developing nuclear weapons. We have no reason to believe that any post-war Japanese government has attempted to develop nuclear weapons. However, as discussed below, that might not always be the case for future governments. But before addressing the question of intentions, let us first consider the question of capabilities.

(a) Japan's Fissile Material Production Capability
Any country wishing to obtain nuclear weapons must gain access to fissile material.1 The two available routes are enriching uranium and extracting plutonium from spent nuclear fuel. Japan has plants capable of carrying out both these processes. Besides the reprocessing facility at Tokai, Japan has plants for enrichment and reprocessing at Rokkasho in the northern tip of the island of Honshu. These plants are owned by Japan Nuclear Fuel Ltd. (JNFL), which is jointly owned by Japan's major power companies.

Japan's enrichment and reprocessing facilities are subject to monitoring and verification under a safeguards agreement with the International Atomic Energy Agency (IAEA). However, although the safeguards applied to Japan's nuclear program are the most extensive and expensive in the world, it is not possible to guarantee that the IAEA's safeguards objectives are met. IAEA's safeguards objectives are defined as "the timely detection of diversion of significant quantities of nuclear material".2

--Missing Plutonium--
To illustrate this point, in 2003 it was discovered that of the 6.9 tons of plutonium separated at the Tokai reprocessing facility in the period from 1977 to 2002, the measured amount of plutonium was 206kg less than it should have been.3 Given that the IAEA defines a "significant quantity" of plutonium as 8kg, this means that since the Carter Administration agreed to let Japan operate the Tokai Reprocessing Facility, enough plutonium has gone missing to make about 26 bombs. After further investigations, the Japanese government claimed that it could explain where some of the missing plutonium had gone and reduced the figure to 59kg, but that is still enough for 7 bombs.

Compared to the 6.9 tons of plutonium separated in the fourteen odd years up to 2002 at Tokai, the design capacity of the Rokkasho Reprocessing Plant is 8 tons per year. That represents a very significant safeguards challenge. Hironobu Nakamura et al of JNFL's Nuclear Material Control Department admitted that in large reprocessing plants, no matter how much measurement precision is improved, detecting "significant quantities" is "problematic" (a euphemism for "impossible"). They said that a simple estimate of "material unaccounted for" (MUF) at Rokkasho could be in the order of 20~30 kgPu at the end of a one year accountancy period.4 Japanese government and industry are quick to stress the other aspects of IAEA safeguards besides materials accountancy, namely containment and surveillance, but materials accountancy remains the central component of IAEA safeguards.5

--MOX--
As mentioned above, the agreement between Japan and the US that allowed Japan to operate the Tokai reprocessing facility involved a compromise. Instead of storing the separated plutonium in pure form, Japan agreed to store it as a mixed oxide of uranium and plutonium (MOX). Japan trumpets the proliferation resistance of MOX, but the IAEA classifies MOX as a "direct use material", which can be converted to nuclear weapons usable form in the order of one to three weeks.6 The process of separating pure plutonium from MOX is chemically straightforward and unirradiated MOX (i.e. before it is loaded into reactors and irradiated as MOX fuel) does not involve the high levels of radiation that discourage separation of plutonium from spent fuel.

--"Reactor Grade" versus "Weapons Grade" Plutonium--
Japan has amassed a total of about 46 tons of separated plutonium, almost 9 tons of which is held in Japan. Based on the conservatively high IAEA value for one significant quantity of 8 kgPu, 9 tons is enough for over 1,100 nuclear weapons. Japan loves to point out that this plutonium is "reactor grade plutonium" not "weapons grade plutonium". However, the term "reactor grade plutonium" is just a label. It does not mean that it cannot be used in nuclear weapons. The IAEA takes the view that any isotopic combination of plutonium, except if it contains more than 80% of the plutonium-238 isotope, is direct use nuclear weapons material.7 In a 2005 report published jointly by Oxford Research Group and Citizens' Nuclear Information Center, Barnaby and Burnie state, "A good nuclear-weapons designer could construct a nuclear weapon from three or four kilograms of the plutonium produced by the Rokkasho-Mura reprocessing plant."8 No one doubts that the plutonium stockpiled by Japan could be used in nuclear weapons and it is dishonest for Japan to suggest otherwise.

--FBR "Super Weapons Grade" Plutonium--
Japan's fast breeder reactor (FBR) program presents an additional proliferation problem. Japan's nuclear fuel cycle policy presumes that at least some of the plutonium separated at reprocessing plants in Japan and overseas will be used in FBR fuel. Due to the failure of the FBR program to date, the government and nuclear power companies decided that some of Japan's plutonium stockpile should be consumed as MOX fuel in light water reactors, but the FBR program has not been abandoned. The current restart date for the troubled Monju prototype FBR is February 2009, although further delays are likely.

A special feature of fast breeder reactors is that they "breed" plutonium when neutrons produced by fission reactions in the reactor core are absorbed by uranium nuclei in a blanket of uranium placed around the reactor. The plutonium thus produced is composed almost entirely of the plutonium-239 isotope. This composition is sometimes referred to as "super weapons grade" plutonium, because it is the most convenient composition for producing nuclear weapons. People should be concerned that if Japan ever succeeds in breeding plutonium in this way it will accumulate a stockpile of this "super weapons grade" plutonium.

--Uranium Enrichment--
The above discussion focused on reprocessing, but Japan also has a uranium enrichment program. The program has been spectacularly unsuccessful from a commercial point of view, but it gives Japan the capability to produce highly enriched uranium (HEU) if it wishes to do so. The purpose of the Rokkasho Uranium Enrichment Plant is to produce low enriched uranium (LEU) for Japan's light water reactors, but it could be reconfigured to produce HEU if a decision were made to do so. Such a reconfiguration might be detected by the IAEA inspectors, but there is no technical obstacle to using the plant to produce HEU for weapons use. Alternatively, the technology developed for the declared plant could be used in a clandestine plant. According to Thomas Cochrane, chief nuclear scientist at the Natural Resources Defense Council, "...a small centrifuge enrichment plant with up to a few hundred centrifuge stages can be readily hidden from the IAEA and from foreign intelligence efforts."9

There is no dispute about the fact that Japan is capable of producing the key ingredients of nuclear weapons, namely plutonium and HEU. If Japan were determined to produce nuclear weapons, it is highly likely that IAEA inspectors would not detect the diversion of plutonium or highly enriched uranium in time to prevent Japan from producing several nuclear weapons. In the end, a large part of the IAEA safeguards system depends on faith. At this point in history, Japan is regarded as a trustworthy state. The following section addresses the question of whether this faith is justified.

(b) Japan's intentions concerning nuclear weapons
Disingenuous claims made by the Japanese government and nuclear industry about the proliferation resistance of MOX and reactor grade plutonium reflect their single-minded determination to develop a "closed nuclear fuel cycle". However, that doesn't mean the Australian government should believe their claims. Rather, their willful misrepresentation of the fact that MOX and reactor grade plutonium are not proliferation resistant should arouse suspicion.

The question that arises is, does Japan have an intention to produce nuclear weapons? The simple answer would appear to be, "Not at the moment." There is no evidence that any post-war Japanese government has had a nuclear weapons program. However, there are reasons to be concerned about the potential for this situation to change at some time in the future.

--Retaining the Nuclear Weapons Potential--
The nearest thing to a smoking gun was a secret Ministry of Foreign Affairs report that stated, "The policy for the time being is not to have nuclear weapons, but the economic and technical potential to produce nuclear weapons will always be retained and care will be taken not to accept any restrictions on this".10 The report was produced in 1969, but its existence only became publicly known through an article published in the Mainichi Shimbun11 on 1 August 1994. On the face of it, this document is hard to reconcile with the "Three Non-Nuclear Principles" first articulated by Prime Minister Sato on 11 December 1967. The "Three Non-Nuclear Principles" are as follows: "not possessing, not producing and not permitting the introduction of nuclear weapons into Japan".12

This apparent inconsistency begs the question, what was the government's real policy? Was the single-minded determination to pursue, in defiance of the wishes of the US government, a problem-prone13, long-delayed and costly14 "closed nuclear fuel cycle" really a single-minded determination to retain "the economic and technical potential to produce nuclear weapons"? On the basis of the publicly available information, it is impossible to do more than speculate, but it is conceivable that both policies co-existed. To legalistically minded bureaucrats, the wording in the Foreign Affairs document might not necessarily contradict the "Three Non-Nuclear Principles". Alternatively, the existence of the two policies might have reflected tensions between a range of views held by different people within the government and the bureaucracy. It would be unfair to the many people who, however mistakenly, believed a "closed" nuclear fuel cycle would assure Japan's energy security to assume that they all shared a secret objective of retaining the option of developing nuclear weapons. Equally, however, it would be naive to assume that the nuclear weapons option played no role in decision makers' calculations.

-- Politicians' Public Statements--
It is beyond dispute that the nuclear weapons option exercises the minds of some elements of the political elite. There is a long list of statements by senior politicians that demonstrate clearly that the "nuclear allergy" attributed to the general Japanese public does not afflict the political elite to the same degree. These statements are usually couched in terms of the need for a debate on the subject.15 In a world where the acquisition of nuclear weapons by non-nuclear weapons states is illegal, one wonders what useful purpose could be served by opening up a debate about something that is out of the question. It is hard to escape the conclusion that the real purpose of such statements is to reduce the resistance to the idea of Japan acquiring nuclear weapons. For the general public this is unthinkable, but it is not unthinkable for the political elite. For example, the official policy of the Liberal Democratic Party (LDP), which has been in power almost continuously since the war, is that possession of nuclear weapons would not be unconstitutional.16 A literal reading of the Japanese Constitution prohibits Japan from having a military in the first place. The original intention of the Constitution has long since been subverted, but the fact that the question of the constitutionality of nuclear weapons ever arose suggests that some people wanted to consider the possibility of obtaining them.

Nevertheless, despite the range of views held by members of the political elite, the Japanese government's official policy remains opposed to the acquisition of nuclear weapons. The "Three Non-Nuclear Principles" remain the official policy to this day (although the third principle has been breached by the US military) and the danger of a nuclear-armed Japan does not appear to be imminent. This is probably the most important point to emphasise.

--The Case of Toshio Tamogami--
That said, a recent scandal involving the Chief of Staff of the Air Self Defense Force (ASDF) raises more questions about the long-term stability of Japan's non-nuclear weapon status. Toshio Tamogami was dismissed for writing an essay which denied Japanese wrong doing in World War II. He has not retracted any of the claims made in his essay and continues to make statements which seem to suggest that he is positioning himself as the leader of the right-wing historical revisionist movement in Japan. Among his many provocative statements, he is reported to have said that Japan should consider developing nuclear weapons.17

It has been said that "Mr. Tamogami's thinking permeates the ASDF".18 It is certainly true that he went out of his way to spread these views within the ASDF. The similarities between Tamogami's views and those spouted in the past by senior members of the LDP, including current Prime Minister Taro Aso and former Prime Minister Shinzo Abe (who appointed Tamogami in the first place) are also disturbing.19 It is frightening to think that Tamogami held these views while serving as ASDF Chief of Staff and even more frightening to think that these views might be widely shared within the Japanese military establishment. It is to be hoped that Tamogami and his views will disappear into obscurity, but given the resonance between his views and those previously articulated by members of the Japanese political elite, that is probably overly optimistic. However, it is vital that the virus that he has helped spread within the ASDF be contained.

In light of the above discussion, it is necessary to put into perspective Japan's policy of "not possessing, not producing and not permitting the introduction of nuclear weapons into Japan". While not disputing that no post-war Japanese government has intended to acquire nuclear weapons, there is no way of guaranteeing that intentions will not change in future. It will depend both on internal factors, including power realignments within the Japanese political system, and external factors, such as the success of negotiations for the elimination of North Korea's nuclear weapons. Above all, in the long term it will depend on the success of negotiations for global nuclear disarmament. In the meantime, the capability that Japan indisputably possesses to produce the ingredients for nuclear weapons, along with the mixed political signals about intentions are reason enough to be concerned about the long-term stability of Japan's non-nuclear weapon status.

2. Implications for Global Nuclear Disarmament and Non-Proliferation

Large-scale reprocessing of the type carried out at the Rokkasho Reprocessing Plant is expensive and technically difficult. However, small-scale reprocessing, if it is not subject to IAEA safeguards and does not prioritise environmental protection or worker health, is a relatively straight-forward chemical process.20 As the weakest link in the nuclear proliferation chain, every effort should be made to discourage reprocessing, which is an unnecessary, uneconomic and polluting addition to any nuclear energy program.

It is hard to see how nuclear weapons can be eliminated in a sustainable way unless reprocessing is eliminated. Seen in this light, the determination of Japan to continue with its reprocessing program is a major barrier to nuclear disarmament. Japan's reprocessing program also makes it much more difficult to persuade other countries to forgo the reprocessing option, thus making it much harder to control nuclear proliferation.

Unlike reprocessing, uranium enrichment is a prerequisite for light water reactor-based nuclear power programs. Uranium enrichment is more technically difficult than reprocessing, but, as the Pakistani and Iranian uranium enrichment programs demonstrate, the technical barrier is not insurmountable for determined states. The more states that develop uranium enrichment capabilities, the more difficult it will be to control proliferation via this route. It is not surprising, therefore, that a December 2008 report commissioned by the US Congress questioned the wisdom of providing financial support for a so-called "nuclear renaissance".21

Japan's uranium enrichment program is now at a turning point. Its official capacity is 1,050 ton-SWU/year, but in fact only one of the plant's seven cascades is still operational and all but a few of the centrifuges in that cascade have been closed down.22 JNFL is preparing to test new centrifuges, which are scheduled to begin operation in 2010, but there is no guarantee that these will work as planned. Considering the problems JNFL has had with the current centrifuges and the problems it is having with the Rokkasho Reprocessing Plant, it is hard to imagine the new centrifuges being an instant success. On commercial grounds, it is hard to see why Japan needs indigenous uranium enrichment technology. On the other hand, Japan's uranium enrichment program provides the perfect alibi for countries like Iran - or Brazil, or any number of other countries that claim they need to be able to enrich their own uranium.

In an attempt to solve these problems, many proposals have been put forward to internationalise the nuclear fuel cycle. Despite the superficial appeal of these proposals, they have not come to much so far. IAEA Director General, Dr. Mohamed ElBaradei, is a great proponent of this approach, but a 2005 report23 which he commissioned identified as many problems as benefits. For example, nothing can make uranium enrichment and reprocessing completely resistant to a so-called "breakout" scenario24, where a country deliberately decides to breach its IAEA safeguards agreement, or to use an international facility located within its territory to produce nuclear weapons material. Furthermore, technical skills gained within multilaterally controlled civil programs can be transferred to weapons programs. For reprocessing at least, it would be far better to give it up altogether. The question of what to do about uranium enrichment is less tractable if one assumes that nuclear power programs will continue to exist for the foreseeable future. Perhaps it is time to reconsider that assumption. Certainly it would be wise to avoid succumbing to pressures to subsidise a "nuclear renaissance".


Notes and References

1 Note that a Fissile Materials Cut-Off Treaty (FMCT) as currently envisaged will not require a cut-off of production of fissile materials in civilian programs.

2 IAEA Safeguards Glossary, 2001 Edition, p.13.
One significant quantity of plutonium is defined as 8 kg of plutonium and 25 kg of highly enriched uranium (p.23). IAEA's general timeliness detection goal is one month for unirradiated direct use material, which includes highly enriched uranium, plutonium, and MOX. (pp.25, 32, 33)

3 Japan Atomic Industrial Forum, "Better Accounting of Plutonium Urged at JNC's Tokai Reprocessing Plant", Atoms in Japan, May 2003, pp.19~20.

4 Hironobu Nakamura, Toshihiko Utsugi, Yoshihiko Noguchi, Hideto Adachi, Tomonori Iwamoto, "Material Accountancy and NDA Approach for U-Pu Co-Denitration Area (MBA-4) at RRP", The 25th Annual Meeting of the INMM (Institute of Nuclear Materials Management) Japan Chapter: Record of Proceedings, 2005 p.203, 207. (Meeting held 11 November 2004, Japanese article.)

5 International Atomic Energy Agency, INFCIRC/153 (Corrected), June 1972
"29. ...the Agreement should provide for the use of material accountancy as a safeguards measure of fundamental importance, with containment and surveillance as importantcomplementary measures."

6 IAEA Safeguards Glossary, 2001 Edition, p.22.

7 IAEA Safeguards Glossary, 2001 Edition, p.33.

8 Frank Barnaby and Shaun Burnie, Thinking the Unthinkable: Japanese nuclear power and proliferation in East Asia, Oxford Research Group and Citizens' Nuclear Information Center, August 2005, p.8.

9 Thomas B. Cochran, "Adequacy of IAEA's Safeguards for Achieving Timely Detection", Chapter 6 in Henry D. Sokolski (Ed.), Falling Behind: International Scrutiny of the Peaceful Atom, Strategic Studies Institute, February 2008, p.133-137.

10 Japanese Foreign Policy Principles ("Wagakuni no Gaikou Seisaku Taikou"), produced in 1969 by the Foreign Relations Policy Committee ("Gaikou Seisaku Iinkai"). The Foreign Relations Policy Committee was an informal committee established within the Ministry of Foreign Affairs in 1968. Translation by Citizens' Nuclear Information Center.

11 The Mainichi Shimbun is one of Japan's leading national newspapers.

12 Refer the following pages on the Ministry of Foreign Affairs website:
http://www.mofa.go.jp/policy/un/disarmament/nnp/index.html
http://www.mofa.go.jp/policy/un/disarmament/nnp/announce.html

13 For information on the problems at the Rokkasho Reprocessing Plant, see articles on the following page of Citizens' Nuclear Information Center's web site:
http://cnic.jp/english/topics/cycle/rokkasho/index.html

14 See the following comment about the cost of the Rokkasho Reprocessing Plant by Liberal Democratic Party Diet Member Taro Kono (currently chair of the House of Representatives Foreign Affairs Committee) in an interview with the Japanese consumer magazine Tsuhan Seikatsu:
"If you divide [the difference in the cost of electricity with and without reprocessing] by kilowatt hours, it works out to a difference of 0.5 yen, but the total difference is 10 trillion yen....If the next plant is built, the cost will be even greater. Already for construction alone 2.1 trillion yen has been spent on the Rokkasho Reprocessing Plant. That is 3 times the original estimate of 0.7 trillion yen. In the end it is the consumers who will have to foot the bill." (Spoken in response to comments by Hajimu Yamana of Kyoto University.)
"Heated Debate: Considering Japan's Energy Problem - Should the Rokkasho Reprocessing Plant be Operated or Abandoned?" (An interview which took the form of a debate between two supporters (Taro Kono and Hitoshi Yoshioka) and two opponents (Hajimu Yamana and Kumao Kaneko) of the Rokkasho Reprocessing Plant), Tsuhan Seikatsu No. 234, October 2008, p.205. Published by Catalogue House. (Translation by CNIC.)

15 For example, Taro Aso (then Foreign Minister, now Prime Minister) made the following comment in 2006:
"When a neighboring country is going to have nuclear weapons, one can refuse to even consider the matter," he told a Diet committee. "But I think it is important to discuss the issue."
Quoted in "Aso keen to explore nukes but Abe says debate is 'finished'", The Japan Times, 19 October 2006.

16 Prime Minister Shinsuke Kishi made the following statement in 1957 and prime ministers and senior Cabinet ministers have confirmed this interpretation up to the present day.
"It is not unconstitutional for Japan to possess nuclear weapons, simply because they are called nuclear weapons, provided they are within the definition of self-defence."
Reported in the Asahi Shimbun, 7 May 1957.

17 (1) Extract from Bradley K. Martin, "Ousted Japan Air Force Chief Calls for Nuclear Weapons Debate", Bloomberg.com, 1 December 2008:
http://www.bloomberg.com/apps/news?pid=20670001&refer=japan&sid=aeu.6CmaBEQI
Japan's former air force chief, forced into retirement for denying World War II aggression against its Asian neighbors, said the country should start a discussion on whether to develop nuclear weapons.
"I think there should be debate about this, because nuclear deterrence would be enhanced as a result," Toshio Tamogami, former head of the Air Self Defense Force, told reporters today at the Foreign Correspondents' Club of Japan in Tokyo.
(2) Extract from Julian Ryall, "Japan 'should develop nuclear weapons'", Telegraph.co.uk, 1 December 2008:
http://www.telegraph.co.uk/news/worldnews/asia/japan/3538566/Japan-should-develop-nuclear-weapons.html
Japan should consider developing nuclear weapons, the former head of the Japanese air force has said. And if the country had atomic weapons in 1945, it should have used them against the Allies, General Toshio Tamogami added.

18 "Deviant thinking on defense", Editorial in The Japan Times, 16 November 2008:
http://search.japantimes.co.jp/mail/ed20081116a1.html

19 The denials by Taro Aso and Shinzo Abe of some of the worst aspects of Japan's role during the war are one of the reasons why they are considered hawks within the LDP. For example:
Mr. Aso refused to acknowledge that his family's company, Aso Mining, used hundreds of British and Australian prisoners of war as slaves, until Health Ministry documents confirming this were unearthed in December 2008. ("Taro Aso firm worked Aussies as slaves", The Australian, December 20, 2008: http://www.theaustralian.news.com.au/story/0,25197,24826099-25837,00.html)
Mr. Abe "provoked anger in China and South Korea when he said there was no evidence that women were forced to become sex slaves by the Japanese army during World War II." ("Profile: Shinzo Abe", BBC Web Site: http://news.bbc.co.uk/2/hi/asia-pacific/4392480.stm)

20 See for example Henry D. Sokolski, "Assessing the IAEA's Ability to Verify the NPT" Chapter 1 Appendix II (The Proliferation Dangers of LWRs) in Henry D. Sokolski (Ed.), Falling Behind: International Scrutiny of the Peaceful Atom, Strategic Studies Institute, February 2008, p.58.
"As for chemically separating the plutonium from spent fuel, this could be accomplished in a facility as small as 65 feet by 65 feet...This plutonium separation plant also need not be elaborate. Yet another "quick-and-dirty" design plant, detailed by the nuclear industry's leading experts in the late 1970s...employs technology little more advanced than that required for the production of dairy products and the pouring of concrete."

21 World at Risk: The Report of the Commission on the Prevention of Weapons of Mass Destruction Proliferation and Terrorism, Vintage Books, December 2008.
"Concern about the spread of nuclear weapons intensifies with the possibility of a large increase in nuclear power production to meet growing energy demands-a nuclear renaissance. As additional countries acquire nuclear facilities-particularly if they build uranium enrichment facilities or reprocessing facilities, ostensibly to provide fuel for their power plants and reduce the waste associated with the spent nuclear fuel-the number of states possessing the knowledge and capability to "breakout" and produce nuclear weapons will increase signi_cantly." (pp.14,15)
"The spread of nuclear technology and nuclear material heightens concern that non-nuclear-weapon states might decide to develop nuclear weapons, building on their civilian nuclear industry. It also increases the possibility that terrorists might be able to steal-or buy from an insider-the materials or technical knowledge needed to construct a nuclear weapon. We should discourage, to the extent possible, the subsidizing of nuclear energy in ways that would cause states to choose it over other energy sources, without fully accounting for this risk." (pp.55,56)

22 See the following pages on JNFL's Japanese web site:
http://www.jnfl.co.jp/press/pressj2008/pr080425-1.html
http://www.jnfl.co.jp/business-cycle/1_nousyuku/nousyuku_03/nousyuku_03_02.html
Limited information is also available on JNFL's English web site:
http://www.jnfl.co.jp/english/uranium.html

23 Multilateral Approaches to the Nuclear Fuel Cycle: Expert Group Report to the Director General of the International Atomic Energy Agency, International Atomic Energy Agency, 22 February 2005.

24 Ibid. p.131.
"Whether voluntary or compulsory, multilateral facilities share a potential weakness with their national counterparts, namely the risk of the host country 'breaking out'..."

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