The air got where it needed to be by about seventy-eight, judging by my drives through Ponca City and other refinery towns. Those standards are something the state’s can maintain, and I don’t see any likelihood of any municipalities not maintaining at least those standards today.
Again, it is not a task that requires the federal government or else it won’t happen.
But for the most part I agree the air pollution war has been won and states can do most things but not everything.