“It’s important to aim for zero nuclear power over a 40-year period, gradually, in a realistic manner,” Seiji Maehara, policy director for Japan’s ruling party and a former foreign minister, said in Washington on Wednesday night.

Before the tsunami-induced disaster, Japan had been planning to increase its reliance on nuclear power from 30 percent to as much as 50 percent. With no oil or gas reserves, Japan has long viewed nuclear as a national-security imperative — the only way to reduce dependence on the Middle East, Russia and other unreliable providers.

But, Maehara said at a dinner sponsored by the Japan Congressional Study Group and the Sasakawa Peace Foundation, “Although we were told these plants were absolutely safe, we did have an accident.” Some 343,000 people have had to abandon their homes because of radioactivity, he noted, and at one point during the crisis, the government was contemplating the possible evacuation of 30 million people.

Japan’s prime minister, Yoshihiko Noda, has been bravely swimming against the current on several issues: raising taxes and removing trade barriers as well as reopening most of the nation’s 50 nuclear power plants, which were shut after the Fukushima disaster. Now apparently he has decided on at least a tactical retreat.

Whether zero-nuclear really becomes Japan’s policy remains to be seen. Given how frequently the country discards and replaces its leaders, you can’t count on policy continuity.

But in case you were looking for more things to worry about in the world, here’s some possible effects that aren’t at the top of the debate:

Climate change. Nuclear power creates electricity without releasing greenhouse gases. Japan hopes to replace nuclear power with alternative energies, notably geothermal (though the country’s onsen, or hot-spring, tourism industry worries that such power plants could drain its pools). But in the short run, and quite possibly in the long run too, the effect of abandoning nuclear will increase reliance on climate-warming carbon fuels.

Nuclear safety in Japan. Already since the accident, Japanese universities have seen a decline in students wanting to become nuclear engineers. If the government commits to abolition, that trend will accelerate; what young person wants to embark on a career in an industry condemned to die? But if the government manages to persuade voters to agree to the gradual decline described by Maehara, who will keep the plants safe for the next 40 years?

Nuclear safety around the world. Germany and Japan may give up on nuclear, but the developing world is moving the other way. Who will be the provider of technology? A likely candidate is China, which continues to build nuclear plants at home and will be happy to export its know-how. Does China operate to the same safety standard as Japan, or are the shortcuts revealed by recent bridge collapses and high-speed rail accidents echoed in the nuclear industry? I don’t know — and given the absence of any democratic accountability in China, there’s no way for other outsiders to know, either.