A few years ago the brilliant scientists on the Supreme Court decided, against the objections of the Bush Administration, that the EPA has not only the power, but the duty to regulate greenhouse gas emissions from cars, and everywhere else. The decision was of course hailed by environmentalists and disdained by many others, and provided yet another good argument for limiting the term lengths of Supreme Court justices. There was little disagreement on all sides that the EPA would not stop at simply regulating CO2 in cars, that it would seek to expand its power to regulate ever more aspects of American life under a more sympathetic president.
Early on in the Obama administration the EPA made noises that intended to do just that, and fast, but the subsequent negative reaction in the Congress (including Democrats in energy-producing states) and elsewhere made the agency back down temporarily. At the time, President Obama said he wanted to see this happen, but he would prefer that it be accomplished by the action of Congress. I think it would be safe to say that Obama doesn't feel much constrained in his actions by any antiquated notions about Congressional superiority that may have been originally intended in the Constitution. Heading into the third year of his Presidency, Obama is clearly showing that he intends to bring about his agenda with or without the help of Congress, knowing that if the Republicans actually stiffen their spines and grow a pair, this is the only way he will be able to make that happen. The latest shot in this war is the announced intention by the EPA that it will seize control of the regulation of greenhouse gas emissions from power plants and oil refineries from the state of Texas, after several years of that state's governor refusing to submit to the EPA's demands.
So now the question is, what exactly are the limits on the power of the EPA? It seems to me that the only limit at this point would be for the Congress to deny funding to the agency, short of passing new legislation that explicitly states what the agency can and can't do. Even if there were court rulings against the EPA expanding its power, the past two years have shown us that the Obama administration feels no obligation at all to submit to federal court decisions--the lastest example being the "net neutrality" rules the FCC has announced, even though a federal court has ruled it has no such authority. An earlier instance was the Energy Department ban on off-shore oil drilling, again in defiance of another federal court order.
Maybe this is overstating the case, but I have to wonder if we're still citizens in a constitutional republic, or are we now merely subjects in the United States of EPA.