In a rare bit of good news out of the U.S. Supreme Court, the nation’s highest court ruled 6-2 Tuesday that the Environmental Protection Agency has the right to regulate the smog from coal plants that drifts east across state lines. This is great news for Massachusetts, a state that takes environmental protection seriously but suffers because other states do not.

The decision was so obvious that only Antonin Scalia, who believes the EPA regulations are Marxist for reasons that remain unclear, and Clarence Thomas voted in opposition. The ruling constitutes an endorsement of President Obama’s effort to bypass Republican congressional opposition to any and all environmental regulations by employing the Clean Air Act as a tool for the EPA, and offers hope that this avenue can be used to combat global warming on other fronts.

States like Ohio, Pennsylvania and Michigan that are home to many large coal plants react with a shrug to the unhappiness in New York and New England that their skies are polluted by these plants. Republican legislators in those states barked that the Supreme Court ruling would hurt their economies, but they offered no explanation as to why the EPA or the court would permit coal plants in their states to pollute the atmosphere in other states. There is no defense, and the court decision was, as EPA administrator Gina McCarthy said, "a resounding victory for public health." In a slap at GOP know-nothings, Ms. McCarthy added that the EPA’s regulations are based on "strong legal foundations and sound science."

Coal companies responded to the decision by declaring that it would force them to shut down their oldest and dirtiest power plants. Is that supposed to be a threat? By closing those plants and installing "scrubber" technology to their newer plants, the companies can reduce their chemical emissions to acceptable levels, sparing us their smog.

Massachusetts can now breathe a little easier. And along with the EPA, it can actually thank the Supreme Court for its ability to do so.