TOKYO -- Japan ordered a pair of reactors back online over the weekend for the first time since last year's nuclear accident, but the chaos and confusion surrounding the decision highlight how unready the country may be to restart its atomic-energy engine.

A group of cabinet ministers led by Prime Minister Yoshihiko Noda decided Saturday to restart the reactors, in a bid to wrench the economy back on track, 15 months after an earthquake and tsunami caused devastating meltdowns at the Fukushima Daiichi power plant. The government estimates that if Japan does not turn any reactors back on, its economy could shrink as much as five percent by 2030.

Yet the restart decision comes a month ahead of deliberations over a new energy plan, which could call for phasing out nuclear power for good. And the restarts would come a few months before the setup of a new Japanese nuclear regulator, which will craft new safety guidelines and is expected to take a harder line on vetting reactors.

Opinion polls consistently show more than half of Japanese are opposed to nuclear power, though they fret over energy shortages expected as soon as this summer and higher electric bills if the reactors stay off. Even some of those who favor atomic energy worry the government has not done enough to ensure nuclear plants will be safe from a Fukushima-type accident.

Many businesses have strongly backed restarts, stating the need for stable power supplies.

"We understand that we have not obtained all of the nation's understanding," Industry Minister Yukio Edano said at a news conference Saturday to announce the decision.

The deep national ambivalence is playing out in and around Oi, the western Japanese town that is home to the two first reactors slated to come back online. The mayor of Oi says he is satisfied with the safety precautions taken so far at the plant. Many community leaders in the city of Nagahama, about 40 miles (64km) away, have said they are not.

"It's not that we're against nuclear power," according to Kazumi Mizukami, deputy chairman of a group representing 424 Nagahama neighborhood associations, which on June 5 issued a statement urging their mayor to "thoroughly debate" nuclear safety before going along with reactor restarts.

Mizukami and his group are asking for more drills for nuclear emergencies, more training for the city's first responders and more regular briefings from Kansai Electric Power, which operates Oi and supplied power from other now-idled reactors that are a mere eight miles (13km) from northern Nagahama.

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