All It Took Was a Supreme Court Ruling, a New President and an Economic Crisis ...

Traffic jam on the I-5 leads to dirty air ... and greenhouse gases. (Flickr/Sandy Kemsley)

With all deliberate speed, the Obama Administration's EPA has approved California's four-year-old request to be allowed to regulate climate-changing greenhouse gas emissions from auto exhaust. Today's decision was somewhat anticlimactic, because the parameters were worked out in mid-May when automakers, state and federal regulators and environmental groups sat down together to hammer out the single national standard that the car industry has long said it wanted. (See how that policy might affect your next car purchase.)

What a difference an administration makes for the nation's environmental groups: Instead of stonewalling for more than two years and then denying California's request for the EPA waiver, President Barack Obama brought the stakeholders together to create something that only conservative and libertarian think tanks could oppose.

"After three and a half years, a Supreme Court ruling [that greenhouse gas is a pollutant] and a change of Presidents, this is finally a done deal," said Roland Hwang of the Natural Resources Defense Council.

The decision had been widely expected, and it will give California considerable leverage as the federal rulemaking process begins. The state's Air Resources Board said it will abide by the federal program for the years 2012 to 2016 -- provided it is not weakened by automaker loopholes and closely resembles the agreement announced last month.

EPA Administrator Lisa Jackson was practically holding hands with automakers when she said, in a statement that "this decision reinforces the historic agreement on nationwide emissions standards developed by a broad coalition of industry, government and environmental stakeholders earlier this year."

Michael Stanton, President of the Association of International Automobile Manufacturers, said that the group had expected EPA to grant the waiver. He said the group is now focused on finalizing operational details (a possible source of the aforementioned loopholes) and will "continue meeting aggressive goals for cleaner, more fuel-efficient vehicles."

The devil will be in the details. If automakers attempt, for instance, to use flex-fuel, ethanol-burning cars (which mostly run on gasoline) to meet greenhouse gas mandates, they're likely to have a fight on their hands from environmental groups and state regulators.

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