I am a big fan of the idea of States's Rights. There was a reason why the U.S. Constitution explicitly reserves all unenumerated rights to the states and to the people. The states were intended to be mini-laboratories in democracy. They were supposed to experiment with ideas, and those ideas, if successful, would spread to other states. If they were lousy ideas, and generated lousy results, those ideas wouldn't make it beyond the borders of that state. That way, good ideas could be proven, and bad ideas would be discredited, without screwing up the whole country all at once.
Today, Jonah Goldberg writes about the issue of States' Rights, and how there is rank hypocrisy on the left with regard to the new Arizona illegal immigration laws.