A former Japanese defence minister has urged the country to rethink its prohibition on nuclear weapons in response to threats from North Korea.
Shigeru Ishiba, a leading member of the ruling Liberal Democratic Party (LDP), said Japan needed to discuss its non-nuclear principles, following Pyongyang's sixth nuclear test last Sunday.
Experts say the latest device was up to 10 times more powerful than the American atomic bomb that destroyed the Japanese city of Hiroshima in August 1945.
The three principles, formally adopted in 1971, state that Japan shall neither possess nor produce nuclear weapons, nor permit their introduction into Japanese territory.
Another senior defence official, speaking anonymously to Reuters this week, also suggested that American nuclear weapons be deployed to Japan.
“Perhaps it’s time for our three principles to become two,” he said.
Japanese officials rarely publicly discuss such issues, which remain politically taboo in the only country to have been targeted by atomic bombs.
Just five per cent of Japanese people said they wanted their country to possess nuclear weapons in a poll conducted last year. In South Korea, by contrast, the figure is over 60 per cent.
Japan abstained - reportedly under heavy American pressure - from a landmark global ban on nuclear weapons approved in July at the UN headquarters in New York.
Privately, Japanese officials fret that deterrence against North Korea and nuclear-armed China would suffer without the threat of American nuclear retaliation.
Last year prime minister Shinzo Abe reportedly expressed "concern" that Washington was weighing whether or not to end its controversial option of nuclear first-strike against an opponent.
Japanese officials view discussion on deploying nuclear weapons in the country - or even building an independent nuclear deterrent - partly as a way to jolt China into tightening its vice on North Korea.
One result of accepting Pyongyang’s claims that it has joined the nuclear club could be a deeply destabilising regional arms race, warn some.
“China should realise that there are consequences of its failure to exert its influence over the North,” said an official with Japan’s defence ministry, who requested anonymity.
Then US vice president Joe Biden played a similar card last year. "What happens if Japan, who could go nuclear tomorrow? They have the capacity to do it virtually overnight, he told Chinese president Xi Jinping.
During an interview on Wednesday with TV Asahi, a private network, Mr Ishiba said while “emotionally” he did not want nuclear weapons in Japan, it was time to start a discussion on changing the nation’s military posture.
"Is it truly correct for us to argue that [nuclear weapons] not be placed in Japan while saying that we are protected by the nuclear weapons of the United States, " he said.
The government responded by saying that the status quo had not changed. “We don’t have any plan to begin discussing the three non-nuclear principles,” Yoshihide Suga, the government’s top spokesman told reporters.
