Anybody who watches the trends can see that the tide is turning (maybe already has) on gay marriage, for the reason that Jennifer Rubin identifies -- "because the arguments against gay marriage are no longer persuasive with a significant chunk of the electorate." As more and more states adopt that standard, the pressure will be on the Supreme Court to invoke the Full Faith and Credit Clause of the Constitution to make gay marriage the law of the land. Whether this particular court would go that way is open to debate.
Now comes Texas Gov. Rick Perry, probable candidate for president, with a "let the states choose" approach that can only add to the momentum:
But while Texas has written into its constitution that marriage is defined as being between one man and one woman, he said New York's recent decision to implement same-sex marriage “is New York's prerogative.”
Taking federalism seriously -- especially its foundation of the 10th Amendment -- means accepting the right of states to determine their own course and living with the certainty that some of them will choose paths we wouldn't.
Rubin again:
As I have suggested before, a 10th Amendment approach to gay marriage and abortion is both in keeping with the party's defense of federalism and smart politics. As gay rights moves from the courts to state legislatures and referendums, it will, I would suggest, become increasing difficult for conservatives to decry democratically approved gay marriage laws.