Japan disaster reopens nuclear debate in Europe and US
The immediate concern is how to contain the crisis in Japan's nuclear plants. But thoughts are also turning to the future and, in the world's two big industrial blocs, the politics of nuclear power has already changed.
In Germany, there's already been a long debate about what to do with the country's 17 nuclear power stations. Last October, Chancellor Angela Merkel's government decided, with much opposition, to extend their lives by another 12 years so that the last one is now due to be closed in 2035.
That fractious debate has now reopened.
Mrs Merkel has announced a three-month pause in her previous decision to extend the lives of Germany's nuclear power stations. She said that nuclear power remained an important "bridging technology" between the current system and a greener system of power generation but, she added, "we cannot just go back to business as usual".
"Events in Japan," she said, "teach us that risks that were thought to be completely impossible cannot in fact be completely ruled out."
In two weeks, the voters of Baden-Wuerttemberg go to the polls. This is her natural territory. It has been controlled by the Christian Democrats for decades but Japan's disaster may now change that.
On Saturday, a previously scheduled anti-nuclear demonstration in the region attracted tens of thousands more than expected. That evening, the chancellor met her ministers to discuss the Japanese events and announced that safety standards in Germany would be reviewed.
But her dilemma is how to answer concerns without undoing her policy.
In France, too, the debate has changed.
France gets 75% of its energy from nuclear power, exporting the excess and earning useful currency by so doing.
In addition, some in government want to sell French reactors to emerging economies.
Greenpeace immediately called for a reversal of this nuclear policy which France embraced in the 1970s after the "oil shock" when the price of oil jumped.
The group Sortir du Nucleaire protested by the Eiffel Tower, unfurling banners saying "Nuclear is killing the future".
Daniel Cohn-Bendit, who is a member of the European Parliament for the Green Party, told French radio that there should be a national referendum on the country's dependence on nuclear power. "It begs the question of the need for civil nuclear power," he said. "Is it not time to sound the alarm?"
This is difficult for the government because France's dependence is so great.
Three-quarters of its electricity is generated by nuclear power stations. The country has 58 reactors in 19 plants, second only to the United States in its use of nuclear. In addition, France has been eyeing markets in developing countries which might want to buy reactors.
French industry minister Eric Besson pointed out that France did not have the same risk of earthquake as Japan: "All French nuclear plants have been designed with seismic risk and flooding risk factored in."
But he added (in a phrase which may be a template for pro-nuclear politicians): "We don't wait for an accident to happen in Japan to raise the question over here - but this doesn't mean that we can't re-evaluate the situation."
Austrian environment minister Nikolaus Berlakovich said he would ask his fellow ministers in the European Union to approve "a stress test of nuclear plants" - similar to stress tests on banks where extreme situations are imagined by computers.
In the United States, too, the debate has changed. At the moment, President Obama is in pro-nuclear agreement with Republicans. He believes that nuclear power provides a relatively cheap form of energy, and one which doesn't produce global warming gases like coal, gas and oil-fired power stations do.
Even environmental groups in the United States, unlike in Europe, believe that nuclear power has a place because of its light carbon footprint.
But this was a fragile consensus and it is hard to see how it won't now come under pressure. Over the weekend, Senator Joseph Lieberman told CBS programme Face The Nation: "I think it calls on us here in the US, naturally, not to stop building nuclear power plants but to put the brakes on right now until we understand the ramifications of what's happened in Japan."
The New York Times quotes Jason Grumet, an adviser to President Obama, from the Bipartisan Policy Center in Washington: "It's not possible to achieve a climate solution based on existing technology without a significant reliance on nuclear power."
The United States has recently witnessed disasters with oil in the Gulf of Mexico and coal with the mining disaster a year ago in West Virginia which claimed 29 lives, and both underlined the cost of alternatives to nuclear.
But Japan may tip back the balance of debate. As Mr Grumet put it: "The accident certainly has diminished what had been a growing impetus in the environmental community to support nuclear power as part of a broad bargain on energy and climate policy."
The problem for pro-nuclear governments is that explosions at nuclear reactors in one of the world's most advanced economies must play strongly in the public mind, whatever the assurances of safety and cool calculations of costs, benefits and risk.
The debate has changed.