Maine may be poised to become the next state to require its residents to purchase health insurance. Throw in recent state actions on global warming, including a victory in the U.S. Supreme Court, and you have the basis for a rediscovery and appreciation of the virtues of federalism by the American Left. The difference, however, is that they don’t really favor a diversity of state policies that reflect local community preferences and changing conditions. They simply want states to road-test the jalopies that will eventually be forced on everyone by Washington.