Promises kept and promises broken, such is the world of politics. A person running for a government office will often try to win over the people by promising new changes ahead. A President, though (he) may be forthright in his optimism of change by bringing forth new bills, will often be over-ruled by the Senate. This is the same reason why we had heard about climate change & the need for a new energy strategy, only to not hear much about it since. While it may have been a genuine priority for Obama to address climate change, it's not going to fully come to life when people with financial interests are preventing you from doing so.
Fortunately, an entire body of law exists specifically for environmental issues and thank goodness for that. For without it, this world would have already been destroyed.
Individual States are in the best position to regulate, and have the power to regulate, greenhouse emissions (air pollution) and not necessarily Congress. This is why there are now "no smoking zones" because the States are granted this police power. It is also the job of the EPA ,a federal administrative agency, to carry out this function through directives of the President. The States do their part by incorporating elements of the Clean Air Act into their respective Statutes. This is much like giving the job to the best candidate who can carry it out.
As for the EPA's authority possibly being curtailed, there is certainly no case for that to happen. They are granted Constitutional authority to regulate greenhouse gases. In fact, it is their duty to do so and failing to do is a violation of human welfare. Since they have the authority to regulate emissions, and it is through emissions that global climate is changing, then they have been regulating global climate change through their efforts; and not necessarily through direct policy. In other words, even if they are not directly authorized by Congress to regulate global climate change, they have been doing so all along as an effect of regulating automobile emissions. Just because Congress does not regulate greenhouse gases does not mean that the EPA is not in a position to. The Clean Air Act, which was drafted by Congress, gives the EPA the authority to regulate "climate" in the event that it forms a “judgment” that such emissions contribute to climate change, as carbon dioxide and other greenhouse gases fall within the Act's capacious definition of “air pollutant.” Clean Air Act, § 202(a)(1), 42 U.S.C.A. § 7521 (a)(1)
