Why Japan Just Might Build Nukes

Ask young South Koreans if they're concerned about North Korea's nuclear ambitions, and chances are the conversation will soon turn to a popular novel, The Rose of Sharon has Blossomed. It tells the story of a South Korean scientist who clandestinely helps the North develop a nuclear bomb. Later, North and South Korea join forces to destroy the aggressor threatening their peninsula: Japan.

No wonder, then, that Tokyo is worried about North Korea's nukes. If Pyongyang were to launch a nuclear warhead, a likely target would be Japan, still despised for its brutal rule on the Korean peninsula in the 20th century's first half. "North Korea now regards Japan as its biggest regional threat and the country most likely to go nuclear in the future," says Takashi Hirose, an expert on Japanese nuclear issues.

That has policymakers in Tokyo and beyond considering the once-unthinkable prospect of a nuclear-armed Japan. The U.S. "should remove [its] objections to Japan developing nuclear weapons," said Senator John McCain (R-Ariz.) on Jan. 5. The following day, the Cato Institute, the conservative think tank, recommended that the U.S. reduce its military forces in South Korea and Japan and give both countries a nuclear green light. Even in Japan, some senior politicians have broken a long-standing taboo by discussing the possibility of a nuclear buildup. Yasuo Fukuda, the chief Cabinet Secretary, last June confided to Japanese reporters that "depending on the world situation, circumstances and public opinion could require Japan to possess nuclear weapons." Shinzo Abe, the Deputy Cabinet Secretary, said later that it would be acceptable for Japan to develop small, strategic nuclear weapons.

Granted, there are big legal, cultural, and political barriers to a nuclear Japan. The memory of the atomic bombings of Hiroshima and Nagasaki remains burned into the national psyche, and historically some 80% of Japanese are opposed. Furthermore, Japan would have to amend its constitution, which bans nuclear arms. "U.S. policymakers talk about getting Japan to make nuclear weapons, but it will never happen," insists former diplomat Satoshi Morimoto, now a Takushoku University security expert.

If Japan could get beyond the hurdles, it likely wouldn't need long to develop a bomb. It has five tons of plutonium stored in the nuclear research center of Tokai-mura, north of Tokyo, and its scientists know how to convert it to weapons-grade material. Hideyuki Ban, director of the nonprofit Citizens' Nuclear Information Center, says Japan could build a nuclear bomb within months. And its civilian rocket and satellite launching system could easily be converted to military use. Japan also has superbly equipped land, sea, and air forces that could deliver medium-range nukes to North Korea.

But if Japan decides to build its own nukes, get ready for an Asian arms race. China would likely want to boost its arsenal, which would prompt India to develop more nuclear weapons, which would spur Pakistan to do the same--and on and on into an ever more perilous future.

By Irene M. Kunii in Tokyo

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