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Weapons of Mass Destruction (WMD)

Nuclear Weapons Program

Japan's small size, its geographically concentrated industry, and the close proximity of potentially hostile powers all render the country vulnerable to a nuclear strike. North Korea's attempts to develop nuclear weapons coupled with its capability to target Japan with any weapon that it developed, is a matter of great concern to Japanese military strategists. Events on the Asian mainland could also affect Japan. From the early 1970s, China possessed a nuclear force capable of striking Japan.

Having renounced war, the possession of war potential, the right of belligerency, and the possession of nuclear weaponry, it held the view that it should possess only the minimum defense necessary to face external threats. The Japanese government values its close relations with the United States, and it remains dependent on the United States nuclear umbrella.

Weapon-grade plutonium is nearly pure plutonium 239, whereas the plutonium in commercial fuel is much lower in plutonium 239 and higher in the isotopes that are undesirable for weapons use. This, however, is not a crucial difference, since all plutonium can be used in weapons. The US nuclear weapons arsenal does not utilize commercial (reactor grade) plutonium from spent fuel. Tests were completed, however, to confirm that reactor grade plutonium could be used in a nuclear explosive and is therefore a nonproliferation concern. Some have said the Japanese reactor-grade plutonium would not be fully usable, but the US detonated a reactor-grade plutonium device in 1962, and in order to discourage other countries from using plutonium as a fuel, President Carter declassified data on the feasibility of a reactor-grade plutonium for nuclear weapons in 1976. A nuclear bomb similar to the one exploded in Nagasaki can be made with seven to eight kg of plutonium.

Although possession of nuclear weapons is not forbidden in the constitution, Japan, as the only nation to experience the devastation of atomic attack, early expressed its abhorrence of nuclear arms and determined never to acquire them. The Basic Atomic Energy Law of 1956 limits research, development, and utilization of nuclear power to peaceful uses, and, beginning in 1956, national policy has embodied "three non-nuclear principles"--forbidding the nation to possess or manufacture nuclear weapons or to allow them to be introduced into the nation. Prime Minister Eisaku Sato made this pledge - known as the Three Non-Nuclear Principles - on February 5, 1968. The notion was formalized by the Japanese Diet on November 24, 1971. In 1976 Japan ratified the Treaty on the Non-Proliferation of Nuclear Weapons (adopted by the United Nations Security Council in 1968) and reiterated its intention never to "develop, use, or allow the transportation of nuclear weapons through its territory." However, if Japan believed that "extraordinary events" had jeopardised its "supreme interests", under Article X of the Treaty it could withdraw from the NPT. Such "extraordinary events" could include the acquisition of nuclear weapons by North Korea. Japan could then legally use its plutonium to build nuclear weapons.

During the Sato cabinet in the 1960's, it is reported that Japan secretly studied the development of nuclear weapons. Prime Minister Eisaku Sato secured nuclear protection from the United States in 1965 by exagerating Tokyo's readiness to develop nuclear weapons. In a 29 December 1964 meeting, Sato told US Ambassador to Japan Edwin Reischauer that Japan might develop nuclear weapons. This followed China's first successful atom-bomb test in October 1964.

In 1970 US President Richard Nixon agreed to return Okinawa to Japan by 1972. At that time, Nixon pledged to recognize the "particular sentiment of the Japanese people against nuclear weapons" but reserved the right to consult with Tokyo over their reintroduction in an emergency. The technical agreement was signed on June 17, 1971, the treaty confirmed by the Senate in November, and reversion accomplished on May 15, 1972.

Eisaku Sato, former prime minister of Japan, received the 1974 Nobel Peace Prize mainly in recognition of his opposition to any plans for a Japanese nuclear weapons program and his crucial role in ensuring Japan's signature to the Non-Proliferation Treaty.

On 17 June 1974, Japanese Prime Minister Tsutomu Hata told reporters that "it's certainly the case that Japan has the capability to possess nuclear weapons but has not made them." This remark aroused widespread concern in the international media at that time.

Japan's nuclear power program based on reprocessed plutonium has aroused widespread suspicion that Japan is secretly planning to develop nuclear weapons. Japan's nuclear technology and ambiguous nuclear inclinations have provided a considerable nuclear potential, becoming a "paranuclear state." Japan would not have material or technological difficulties in making nuclear weapons. Japan has the raw materials, technology, and capital for developing nuclear weapons. Japan could possibly produce functional nuclear weapons in as little as a year's time. On the strength of its nuclear industry, and its stockpile of weapons-useable plutonium, Japan in some respects considers itself, and is treated by others as a virtual nuclear weapons state.

Proponents of Japan's plutonium program have raised suspicions by making false and misleading statements concerning the weapons potential of reactor-grade plutonium. In 1993 Ryukichi Imai, former Japanese ambassador for non-proliferation, wrote that the reactor-grade plutonium being shipped from France to Japan " of a nature quite different from what goes into the making of weapons....Whatever the details of this plutonium, it is quite unfit to make a bomb." Hiroyoshi Kurihara, former executive director of Power Reactor & Nuclear Fuel Development Corporation (PNC -- Japan's primary company for developing plutonium-fueled reactors) stated that "many Japanese experts express the opinion that reactor-grade plutonium could not be used for workable nuclear weapons."

With the Non-Proliferation Treaty being extended indefinitely in 1995 and a heightened awareness of the risks of proliferation, it became increasingly important for the the Power Reactor & Nuclear Fuel Development Corporation (PNC) to gain a better understanding of domestic and international factors involved in these issues and to consider specific measures to promote non-proliferation.

In 1995 the Japanese government conducted an internal study on nuclear weapons options. This analysis reaffirmed previous studies, concluding that developing nuclear weapons would damage Japan's national security and regional security. Initiated in the wake of the 1994 nuclear crisis on the Korean Peninsula, the Defense Agency compiled a 31-page secret report during the administration of socialist prime minister, Tomiichi Murayama, whose party was strongly opposed to even maintaining armed forces before coming to power in 1994. "The discussion in favor of owning nuclear weapons lacks sufficient study into the negative impact, while the idea that not possessing nuclear weapons is detrimental is not sufficiently backed by military theory," the report said. The fact of the existence of the report was disclosed by the Asahi Shimbun on 20 February 2003. The outlines of the study were confirmed by Japanese Defense Agency spokesman Manabu Shimamoto, who stated that Japan had rejected a similar plan to starting a nuclear weapons program in a 1967-1970 study.

In 1998 the restructuring of nuclear R&D in Japan led to the dissolution of the Power Reactor & Nuclear Fuel Development Corporation (PNC) and its replacement by the new Japan Nuclear Fuel Cycle Development Institute (JNC). All responsibilities and commitments related to non-proliferation performed by PNC were taken over by JNC.

In October 1999, Shingo Nishimura, parliamentary vice defense minister and well-known hawk, resigned after stirring up trouble by suggesting Japan arm itself with nuclear weapons. Nishimura had scared a conservative governing leadership that actually agreed with much of what he was saying about nuclear weapons and military policy. Prime Minister Keizo Obuchi categorically denied that Japan was changing its policy against developing its own nuclear deterrent.

On 06 April 2002 Liberal Party president Ichiro Ozawa created a furor claiming that Japan - to deter Chinese threats - could produce "thousands of nuclear warheads" from plutonium extracted from the spent fuel of its more than 50 commercial nuclear reactors. Ozawa said that "if [China] gets too inflated, Japanese people will get hysterical. It would be so easy for us to produce nuclear warheads-we have plutonium at nuclear power plants in Japan, enough to make several thousand such warheads..[I]f we get serious, we will never be beaten in terms of military power."

On 31 May 2002, Chief Cabinet Secretary Yasuo Fukuda became the most senior Tokyo official to publicly discuss Japan's acquisition of nuclear weapons. Fukuda said Japan's peace constitution did not preclude nuclear weapons, and that the times have "changed to the point that even revising the constitution is being talked about." He suggested that "depending upon the world situation, circumstances and public opinion could require Japan to possess nuclear weapons."

According to an article printed in the Asahi Shimbun newspaper on 17 March 2003, US Vice President Richard B. Cheney apparently stated that North Korea's development of nuclear weapons and missiles may trigger an arms race in East Asia, and that "Japan may be forced to consider whether or not they want to readdress the nuclear issues."

Japan is rethinking its defense policy. Prime Minister Koizumi is leading efforts to expand Japan's defense role. Japan's self-defense force won Diet approval recently of purchasing long-range strike aircraft, including four 767 tankers; power projection, including the formation of an air brigade; and missile defense, including software, hardware and AEGIS class cruisers.

Japan's perception of the North Korean threat is growing. North Korea shot a No Dong missile over Japanese territory in 1994. They shot a Taepo-dong missile over Japan in 1998. In December Japanese Coast Guard vessels clashed with North Korean spy boats.

There is a nuclear debate beginning in Japan. In April 2003, opposition leader Ichiro Ozawa openly discussed the nuclear option. In May, Chief Cabinet Secretary Fukuda generally hinted at revising defense doctrine. And last month, Defense Minister Ishiba stated Japan might conventionally strike North Korea first.

Japan's nuclear arsenal would quickly outpace China's. France's nuclear submarine costs just $13 billion and would be well within Japan's means. And Japan nuclear armament would encourage other Asian nations to also arm, even Taiwan.

In October 2004 a panel of academics, business leaders, and former government officials called for Japan to consider acquiring the ability to launch pre-emptive military strikes. That would move the country away from its purely defensive security policy. The recommendations from the panel will strongly influence the government's official defense review, expected to be issued in December 2004. It is only the third such review since Japan's defeat in World War Two. By far the most controversial proposal recommends that Japan obtain a first-strike capability, allowing it to hit enemy missile bases to prevent an attack. That recommendation, if adopted, would be certain to anger Asian neighbors, especially China and North Korea. The panel, however, came out against Japan having nuclear weapons, saying it must not pose a threat to neighboring countries.

"As a signatory to the Nuclear Non-Proliferation Treaty (NPT), Japan has forsworn nuclear weapons. Furthermore, successive Japanese governments have consistently upheld the position embodied in the three non-nuclear principles and that same position underlies the Atomic Energy Basic Law. In a small country like Japan where population and industry are heavily concentrated, the notion of combating nuclear weapons with nuclear weapons makes little sense. By relying on a ballistic missile defense system, Japan can complement America's nuclear deterrent. Furthermore, the Integrated Security Strategy proposed in this report envisages no strategic need for possession of nuclear weapons and, indeed, regards them as undesirable because of the risk they pose in aggravating the international environment."

Japan abandoned nuclear power following the March 2011 earthquake-triggered tsunami with caused multiple meltdowns at the Fukushima nuclear plant. However, the Japanese government later decided to start reactivated the countries 48 reactors because of an energy shortfall. Sendai nuclear power plant in the southern Kagoshima Prefecture cleared an initial safety hurdle in mid-2014, an essential step in the reactivation process.

Washington has banned Seoul from enriching and reprocessing nuclear fuel because of proliferation concerns. The Korean government is pushing for a renegotiation to the agreement.

Henry Sokolski, executive director at the Nonproliferation Policy Education Center, urged the House Foreign Affairs committee to hinder the reopening of the nuclear reprocessing facility in Rokkasho, North Japan. The plant itself was supposed to begin operations in October 2013, but its reactivation was delayed by new safety regulations. The operators of the facility, which, according to the IAEA, has an annual capacity of 800 tons of uranium, or 8 tons of plutonium, say it should be up and running by this October. "If Japan ever decided to open its large reprocessing plant at Rokkasho, it would be producing roughly 2,000 bombs' worth of nuclear weapons-usable plutonium a year," Sokolski told the committee in a hearing in July 2014. "This would almost certainly prompt South Korea to initiate nuclear enrichment or reprocessing of their own as a hedge or weapons option."

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