It's a change of weather, all right. Whoever the next president is, he or she will support federal laws that regulate greenhouse-gas emissions. In speeches this week in Oregon, Sen. John McCain came out for the idea, joining Sens. Barack Obama and Hillary Clinton.

McCain's plan is more business-friendly than those of his two Democratic rivals for president. But this general agreement signals a welcome and needed swing away from the stubborn policies of the Bush administration.

It's hard to overstate the coming change in the White House. Early on, Bush administration members actually denied global warming.

But as evidence grew along with the temperature, the

political

climate changed: All sorts of voters, liberal and conservative alike, accept global warming and want something done. Businesses everywhere already are scenting the air and going green.

The Bush administration has backed down some, but it remains out of step.

To give McCain credit, he has long separated himself from Bush on climate issues. On Tuesday, McCain said the United States could "lead and not obstruct" efforts to limit emissions. Science can't say for sure human activity is the main driver behind global warming - but why add stress to an already stressed biosphere?

Like Clinton and Obama, McCain favors a "cap-and-trade" scheme. Government sets limits on pollution; polluters get credits if they clean up, or pay if they bust the limits. It's a way to create free-market incentives for reducing pollution.

McCain's proposal is hardly bold, but he may have a better chance of wangling it through Congress.

Meaningful reductions would mean painful discipline that nobody seems prepared to adopt. Clinton and Obama are closer to the mark, but each, if president, would face a huge task to get anywhere near it.

A last glimpse of the old, fading Bush way came Wednesday, in a sly ruling on polar bears. Secretary of the Interior Dirk Kempthorne said he will list them as threatened under the Endangered Species Act. But he ordered that this ruling could not be used "to regulate greenhouse-gas emissions from automobiles, power plants, and other sources" - like drilling for oil where the bears live.

In other words, the bears are threatened, but that can't be used to change any policies.

That's precisely the blindered approach to climate change that has frustrated so many. At least with all three presidential hopefuls calling for greenhouse caps, the Bush way now seems endangered.