Analysis & Opinions - Foreign Policy

Tokyo and Washington Have Another Nuclear Problem

| Aug. 17, 2017

This week, Japanese Foreign Minister Taro Kono and Defense Minister Itsunori Onodera are meeting in Washington with their U.S. counterparts, Rex Tillerson and James Mattis, to discuss how the United States and Japan should respond to the latest North Korean provocations. This is wise; only through close cooperation with Japan and South Korea, and by working with China, will we be able to address effectively the nuclear threat Pyongyang poses.

That said, these officials ought to contemplate another longer-term and yet potentially grave nuclear threat — the growth of plutonium production capacity in Japan, China, and, perhaps South Korea. Although this problem is complicated, its solution, if we act cooperatively now, is not. The trick is to move soon.

Japan is planning to open a massive spent reactor fuel reprocessing plant at Rokkasho in the fall of 2018. It is designed to produce 8,000 kilograms of weapons-usable plutonium, enough to make more than 1,000 nuclear weapons a year. The ostensible reason for operating this plant is recycling spent fuel to supply power reactors and a fast reactor. There is only one problem: Japan only has five reactors on line and just terminated its only fast reactor project. In short, there is no way Japan can operate Rokkasho without piling up tons of plutonium for years on end.

China, meanwhile, has just agreed to purchase a similarly sized plant from France, although a massive protest against the first site chosen forced Beijing to defer construction. Still, China wants to have the plant operating by 2030 to fuel a fast reactor it plans to operate sometime between 2040 and 2050. Here, again, the problem is that for a decade or more, China will be producing about 8,000 kilograms of nuclear-explosive plutonium annually. By 2040, it would have enough plutonium stockpiled to make more than 10,000 nuclear weapons.

Why does this matter? China already is estimated to have hundreds of nuclear weapons and enough plutonium to make hundreds more. That may seem like a lot, but if it ever wanted to become a peer competitor with either Russia or the United States, it would need to stockpile several thousands of bombs’ worth of additional fissile material. If Beijing wanted to do this without appearing militarily provocative, the “peaceful” pursuit of a fast reactor program could suffice.

Finally, there is South Korea, which has long complained that Washington has prohibited Seoul from reprocessing U.S.-origin spent reactor fuel, although Japan is permitted to do so. South Korea’s new president, Moon Jae-in, is an opponent of nuclear power plants and may not continue to push for such rights under the U.S.-ROK civilian nuclear cooperative agreement. His political opponents (Moon won his election with only a 40 percent plurality), however, are eager to secure such an option. Indeed, some opposition party figures have spoken openly of a South Korean nuclear weapons option.

Not surprisingly, all of this plutonium production planning has raised regional fears and antipathy. Japanese officials privately insist South Korea has no need to recycle plutonium. They also worry about China’s program. Beijing, meanwhile, complains publicly about the nuclear weapons threat Japan’s plutonium program presents, and are concerned about what the United States might permit South Korea to do.

Fortunately, there is a simple fix. The Trump administration, which has zeroed funding for a U.S. capacity to make plutonium-based reactor fuel, should encourage Japan along with China and South Korea to defer proceeding with their own planned programs. Why? It would save all of these countries hundreds of billions in unnecessary additional spending on money-losing forms of nuclear energy. It also makes political sense: China is having difficulty selling the construction of its reprocessing plant to its public, South Korea now wants to slow down its nuclear efforts, Washington needs a winning cooperative effort as it struggles to sort out North Korea with our allies and China. Meanwhile, Japan’s plutonium program makes neither technical nor economic sense.

This brings us back to that Japanese delegation visiting Washington. As already noted, it includes Foreign Minister Taro Kono. He is one of Japan’s fiercest and most articulate critics of Japan’s plutonium program. Last year, Prime Minister Shinzo Abe asked Kono to look for ways to cut the Japanese government’s budget. Kono recommended terminating the Monju fast breeder reactor, and Abe apparently agreed.

When asked in his first press conference if there should be consultations before the U.S.-Japan civil nuclear cooperative agreement automatically renews in July of 2018, Kono agreed and said they should focus on the security problems Japan’s plutonium program presents. Earlier this year, Kono went further, signing a joint statement urging the Japanese government to defer opening Rokkasho, consult with Washington over its nuclear cooperative agreement, and work with the United States, South Korea, and China to put a pause on the commercial production of plutonium.

North Korea is an important problem, but it is not the only nuclear issue in Northeast Asia. If the United States, China, Japan, and South Korea can head-off a plutonium production capacity race, they will not only make joint action on Pyongyang’s nukes easier, they will prevent a potentially deeper crisis in the future. This too should be on the agenda for Secretaries Tillerson and Mattis.

For more information on this publication: Belfer Communications Office
For Academic Citation: Tobey, William and Henry Sokolski.“Tokyo and Washington Have Another Nuclear Problem.” Foreign Policy, August 17, 2017.

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