The Supreme Court ruled today that six states cannot, for now, try to limit emissions of greenhouse gases under federal common law. The court ruled 8-0 -- Justice Sonia Sotomayor was recused -- that the Clean Air Act and the Obama administration's efforts to regulate emissions had displaced the states' federal common law argument. But the court split, 4-4, on the potentially key issue of whether federal courts even had jurisdiction to hear the claims. The split means the 2nd U.S. Circuit Court of Appeals' finding that it did have jurisdiction stands, although that conclusion would not apply to other...