The Trump EPA has done something historic. It repealed the 2009 endangerment finding, the legal linchpin behind nearly two decades of costly climate regulation that was never authorized by Congress. The repeal is legally sound, long overdue, and directly in line with what the American people voted for. This repeal will save average Americans a lot of money every year and give us more choices just about everywhere. 

So why is the Department of Justice making arguments in federal court that could blow it up?