The technical ins and outs of this are that the EPA's decision to regulate derives from a suit about whether the Clean Air Act includes greenhouse gases, which was clearly not in the mind of the Congress that passed it, but after years of litigation the Supreme Court held it did indeed have to regulate them, as broadly as the statute was written (Wrongly in my opinion, but my vote doesn't count). That was at the end of the Bush adminstration, and his EPA had been fighting having to do it against a cabal of enviro-nuts and Gorebots who insisted they did. Unfortunately Congress had changed hands and then so did the Presidency, so we were screwed. The fix is easy, amend the CAA to exclude greenhouse effect, if any, as a covered issue and limit the definition of polluting gases to those with a direct toxic effect, such as proven carcinogens, perhaps specifically excluding emissions of H2, O2, N2, and CO2 and the noble gases as natural atmospheric components.
This is why cleaning out the Senate and getting a Conservative President (NOT just a Republican Gorebot like McCain) in the White House is so critical. Except perhaps for health care, the greenhouse gas regulation is going to do more damage to the US economy in the long run than any other single piece of Democrackhead mischief.