On the day that two of the three candidates for governor of Minnesota called for an end to the moratorium on new nuclear reactors in the state, emergency officials conducted a disaster preparedness drill at the Prairie Island nuclear reactor.

The convergence of disaster drills and politicking on nuclear power may have been only coincidental. But the timing was instructive: Political pandering is hazardous.

Republican Tom Emmer and Independence Party candidate Tom Horner both told a business audience during a debate Tuesday that they would push to overturn the state's 1994 moratorium on new nuclear plants. DFL candidate for governor Mark Dayton did not join the pronuclear chorus, but his running mate, state Sen. Yvonne Prettner Solon, authored legislation to lift the ban that almost passed last session.

It would be easy to dismiss the candidates' nuclear dancing as political palaver, meant to please a small audience without being taken seriously. But it would be a mistake to underestimate the situation: Behind the scenes, business and labor interests have been pushing quietly to unlock the nuke box in Minnesota.

The state's nuclear moratorium passed in 1994 to balance the industry's demands for expansion of "temporary" nuclear waste storage at Prairie Island. The stakes of that debate -- much of which took place behind closed doors -- were so big that when the Prairie Island Sioux tribe tried to buy 30-second TV spots opposing expansion, the ads were refused by TV stations afraid of offending powerful interests.

Reopening the nuclear question is unlikely to prove easier today: With a host of unsolved problems and divided public opinion, anyone who thinks it would be a snap to build a new nuclear reactor in Minnesota is either a simpleton or a candidate for governor.

Even if everyone is on board, building new nuclear power is all uphill: The city of San Antonio agreed to buy a share of a proposed plant only to drop out when costs skyrocketed from $13 billion to $18 billion -- a surge that explains why investors are cool toward nuclear power and why they want Washington to cover the costs.

Minnesota's two nuclear power plants on the Mississippi at Red Wing and Monticello have reached the outer limits of their originally expected 40-year life spans as Congress and the energy industry decide how to try to revive nuclear energy. President Obama supports nuclear power, and Congress has set aside billions to fund as many as four plants to demonstrate new, safer technology, but there is a thicket of interconnected safety, waste and financial problems to solve.

The Union of Concerned Scientists has criticized the plans to restart the nuclear industry (the plan calls eventually for 100 new plants), calling nuclear power a safety and security problem and a trillion-dollar boondoggle that is not necessary to save the planet from global warming. The UCS says using renewable energy sources and increasing energy efficiency is enough to reduce global warming and warns that the taxpayers would end up bailing out an industry too risky for Wall Street.

Closer to home, the Minnesota Environmental Partnership, a coalition of 80 environmental and conservation groups, opposes ending the moratorium. And St. Paul-based Fresh Energy, a nonprofit group promoting clean and efficient energy use, recently concluded an intense, yearlong study of the nuclear dilemma. Fresh Energy argues that the moratorium should stay in place while renewable fuels and energy efficiencies are pursued. The nuclear moratorium, the group argues, cannot be discussed as a "standalone" issue.

"Nuclear power's future is very uncertain," says Fresh Energy's executive director, Michael Noble. "At this point, it's foolish to describe yourself as either 'pro-nuclear-power' or 'anti-nuclear-power.' We don't know whether nuclear power is at the end of the road, or if it's possibly the technology of the future. The jury is still out."

That jury has been out for a long time. And it is likely to stay out a while longer.

I was on hand, as a reporter for this newspaper, at the time of a 1979 nuclear leak at the Prairie Island plant that led to the evacuation of the plant. (No one bothered to inform the Prairie Island Sioux that an emergency had occurred). Afterward, nuclear supporters joked about the leak: "A Little Nukey Never Hurt Anyone" was the slogan on one postemergency T-shirt I saw being worn in Red Wing.

That accident came shortly after the accident at Three Mile Island but before the 1986 Chernobyl disaster that put a kibosh on the nuclear power movement. We are stuck in that era still, without fixes to the problems we found we had then. Nuclear technology may be "safer," but its related problems seem as difficult as ever to solve.

So be careful when you hear politicians beating the drum for nuclear power.

Don't buy a pig in a poke.

Especially if the pig glows in the dark.

Nick Coleman is at nickcolemanmn@gmail.com.