In 1997, Japan issued a written commitment to the International Atomic Energy Agency (IAEA) that all its separated plutonium would be used in reactors and no amount of surplus materials would be accumulated. At first, Japan hoped to use the separated plutonium for fast reactor purposes, but frequent accidents at its Monju fast reactor halted the effort. Its commercial fast reactor project is also unfeasible. Thus, Japan transformed part of its plutonium into mixed oxide fuel used in light-water reactors to show the commercial value of its separated plutonium. However, this project is also not going so well.
After the Fukushima nuclear accident in 2011, there have been waves of anti-nuclear demonstrations in Japan. Many of the country's nuclear power plants have been closed, making the development of a fast reactor more difficult. With its nuclear power policy shelved, it is more difficult for Japan to justify its vast amount of plutonium storage. Japan's commitment to the IAEA appears to be an empty promise.
Of greater concern to the international community is that Japan has long been committed to advancing its nuclear fuel cycle technologies. Moreover, it is the only non-nuclear-weapon country with production capacity and facilities for enriched uranium as well as plutonium. If the facilities at Japan's Rokkasho nuclear-reprocessing plant are all used to produce highly enriched uranium, its annual production volume could reach 6.4 tons. It is therefore necessary to ensure that the plant falls under IAEA inspections and produces only low-enriched uranium for reactors.
In addition, Japan's decision to build a nuclear-reprocessing plant in Rokkasho has worried the world. By purchasing reprocessing services from Britain and France, Japan has already stored a great amount of separated plutonium. But the Japanese Government still insists on building its own nuclear-reprocessing plant with a total investment of $21 billion. The full capacity of the Rokkasho nuclear-reprocessing plant is projected to reach 9 tons of separated plutonium annually, equivalent to the total current separated plutonium storage of Japan. This large amount of plutonium could be used to make about 2,000 nuclear bombs every year. Without a clear plan for the peaceful use of plutonium, Japan continues to strengthen its reprocessing capacity. There is reason to believe that Japan intends to enhance its nuclear weapon latency.
The Japanese Government introduced the "three non-nuclear principles" in 1967, stating that Japan will not produce, possess or allow the entry of nuclear weapons. These principles and its pacifist Constitution have become the cornerstones of Japan's post-World War II development. However, in recent years, calls for acquiring nuclear capability in Japan have gradually grown. The attitudes of its top officials toward its nuclear policy are especially worrying.
In 1994, then Japanese Prime Minister Tsutomu Hata declared that Japan has the capability to possess nuclear weapons. In May 2002, then Prime Minister Junichiro Koizumi affirmed that Japan would adhere to the three non-nuclear principles, but added that the country did possess the technology to make nuclear weapons. Then Deputy Chief Cabinet Secretary and current Prime Minister Shinzo Abe even said, "Undoubtedly, Japan will have small atomic bombs in the future." This alarming statement, coupled with the increasingly right-wing atmosphere in Japan, is bound to create uneasiness in the international community.
In sum, Japan on the surface actively promotes the three non-nuclear principles and is willing to accept IAEA guidelines; at the same time, however, it is trying to construct a complete nuclear technology system relevant to nuclear weapon production at great expense under the cover of developing nuclear power. Japan has also developed solid-propellant rocket technology, laying a foundation for making long-range missiles to deliver nuclear warheads. With these steps, it has been publicly recognized as a nuclear-hedging country.
After returning the separated plutonium to the United States, the Japanese Government should take further measures to postpone starting its Rokkasho nuclear reprocessing plant. It should also make concrete plans to gradually eliminate the surplus separated plutonium storage at home, and subject itself to international verification. Only by taking these steps can Japan earn the trust of the international community through actions rather than rhetoric.
The author is executive chief for arms control and military strategy at the China Institutes of Contemporary International Relations
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