Never underestimate the Bush administration's ability to stick its fingers in its ears and sing "Doop dee doop de doop":
The White House in December refused to accept the Environmental Protection Agency’s conclusion that greenhouse gases are pollutants that must be controlled, telling agency officials that an e-mail message containing the document would not be opened, senior E.P.A. officials said last week.
The EPA was responding to last year's ruling in Massachusetts vs. EPA, where the Supreme Court ordered the agency to figure out whether greenhouse gases represented a danger or health to the environment. EPA's staff not only said, "Umm... yes," to that one, but argued that the existing Clean Air Act could be used in certain sectors of the economy to regulate greenhouse gases. (I assume this means transportation, though maybe large electric utilities, too.) The staffers also offered evidence that sharply curbing auto emissions could produce up to $2 trillion in benefits over the next 32 years (and that fuel-economy standards could be increased far beyond the 35-mpg-by-2020 required by current law).
Naturally, this didn't go down smoothly with White House officials, who just decided never to open the e-mail and instead pressured the agency to release a scrubbed version that doesn't actually conclude anything. Nothing about the Clean Air Act. Nothing about $2 trillion in benefits. So, right now, a bunch of angry Congressmen—Henry Waxman's carrying the lead pitchfork—want to know how said scrubbing went down, who wielded what sponge, and so forth, but the White House has been only grudgingly handing over documents.
Granted, relying on older laws like the Clean Air Act probably isn't the most efficient way to regulate carbon-dioxide emissions (one energy lobbyist recently described this approach to me as "the ultimate square-peg, round-hole solution," and I'm not sure I disagree). But from a climate perspective, it may be better (and less costly) than inaction. So far, the Bush White House has managed to prevent the agency from using those laws to tackle greenhouse gases by simply muzzling the staff, but if, say, Barack Obama got elected and gave the EPA the go-ahead, you could see a lot of industry groups decide they'd much rather push for a cap-and-trade bill from Congress than deal with, say, a thicket of citizen suits under the Endangered Species Act.