Japan’s Gigantic Stockpile of Plutonium

On Monday, Beijing said it was “extremely concerned” that Japan had resisted returning more than 300 kilograms of plutonium, most of it weapons-grade, to the United States. The material, purchased from America in the 1960s for research purposes, is enough to make 50 nuclear weapons.

Some think Tokyo will agree to hand back the fissile material in March, at the Nuclear Security Summit in The Hague. Even if it does so, the loss will hardly put a dent in its stockpile: the Japanese possess 44 tons of plutonium. Three-quarters of this fissile material is stored in other countries, but Japan has kept 10 tons on its own soil. Those 10 tons are enough to build about 1,500 nuclear weapons.

Japan has more plutonium than any other state that does not have an arsenal of nukes. How did it acquire so much of the world’s most dangerous element? It is the only non-nuke arsenal state that reprocesses plutonium. It reprocesses the material for fuel for its reactors, but the country has shut down all its nuclear power plants in the aftermath of the March 2011 Fukushima Daiichi disaster, Japan’s Chernobyl. So Japan, at least at this moment, has virtually no power-generation need for its gigantic store of plutonium.

This anomalous situation has led its neighbors, and not only China, to question the size of its hoard. Even the US, its ally, is concerned. Steve Fetter says that Japan’s neighbors think the plutonium is “a type of nuclear deterrent—a signal that Japan could quickly build large numbers of nuclear weapons if it chose to do so.”

Fetter, a former Obama White House official, is right about that. But he gets things backwards when he adds: “If other countries perceive a growing Japanese plutonium stockpile as a latent nuclear weapon capability, this will contribute to instability in East Asia.”

East Asia is already unstable, and countries are now trying to defend themselves. Tokyo is a signatory to the Nuclear Nonproliferation Treaty, and as such has promised not to build or possess atomic bombs and warheads. But by maintaining such a large stock of plutonium, the Japanese government appears to be signaling that it has the option to build nukes, should it deem them necessary.

President Obama wants to rid the world of these weapons—and he deserves credit for trying to do so—but his weak policies are actually encouraging their proliferation. China has been transferring nuclear technology since the 1970s, first to the Pakistanis and, through them, to the North Koreans and the Iranians. It has continually violated its obligations under the NPT, as the worldwide anti-proliferation pact is known, to not disseminate nuclear weapons technology and materials.[More-World Affairs Journal]