The government denials continued, even after former Japanese prime minister Yasuhiro Nakasone wrote in his 2004 memoirs that, as defense chief, he had ordered a secret study of Japan’s nuclear arms capability in 1970. The study concluded that it would take five years to develop nuclear weapons, but Nakasone said he decided they were not needed, again because of US protection.
In 2010, the Democratic Party of Japan, after breaking the Liberal Democratic Party’s half-century grip on power, reversed past denials and acknowledged the discussions had taken place.
Given the secretive past, former diplomat Tetsuya Endo and others are suspicious about the June amendment adding “national security” to the atomic energy law.
Backers of the amendment say it refers to protecting nuclear plants from terrorists. Opponents ask why the words are not then “nuclear security,” instead of “national security.”
Japan has 45 tonnes of separated plutonium, enough for several Nagasaki-type bombs. Its overall plutonium stockpile of more than 150 tonnes is one of the world’s largest, although much smaller than those of the US, Russia or Great Britain.
Tokyo Governor Shintaro Ishihara, an outspoken conservative, has repeatedly said Japan should flaunt the bomb option to gain diplomatic clout. Former Japanese prime minister Shinzo Abe has expressed similar sentiments, although in more subdued terms.
That kind of talk worries Japan Atomic Energy Commission Vice Chairman Tatsujiro Suzuki, who runs the government panel that shapes nuclear policy. Himself an opponent of proliferation, he said that having the bomb is a decades-old ambition for some politicians and bureaucrats.
“If people keep saying [nuclear energy] is for having nuclear weapons capability, that is not good,” Suzuki said. “It’s not wise. Technically it may be true, but it sends a very bad message to the international community.”