A lot of time also has been spent debating whether Congress unconstitutionally usurped its own law-making power. But the core issue, we believe, is the matter of costs and benefits. Nobody wants dirty air. Pollutants, after all, can cause health problems. But Justice John Paul Stevens missed the point when he complained that critics wanted clean air only if it doesn't cost too much.
Government has many responsibilities and a finite reservoir of money.
When substantial air quality improvements can be achieved, even at a high price, few object. The Clinton administration's defense was that the EPA had been reasonable in the past. But that is a matter of opinion, and also is irrelevant. Any agency can abuse the taxpayers unless its power is restricted. In the short term, the high court needs to make clear that cost always is a consideration.