If we left marriage to the Fed, there would be no married LGBT couples

Lots of people are complaining that Obama did not make a sweeping statement that the Fed should define marriage, rather than leave it to the states.  But what he did was very canny. From EJ Graff: 

Here's the truth: If we had national marriage laws, I would not be married right now.

The U.S. has only recently been able to break through and try out same-sex marriage, which is leading people to realize, albeit slowly, that it's no threat to anyone. But that's only been possible because our federalist marriage system allows each state to make its own decision. And because we have a federalist system, LGBT advocacy groups are able to challenge the one national marriage law that the U.S. has passed: the Defense of Marriage Act (DOMA).
....
But getting people there requires time. Some parts of the country have been more willing than others to extend that gender-neutral, equal marriage philosophy to marriage's entrance requirements. And what all the DOMA lawsuits are saying to the federal courts is this: let the states decide. The federal government has no power to write marriage's rules, or to pick and choose which marriages it likes and which it doesn't. The federal government's only power is to apply its own decisions—on such things as pensions, health insurance, immigration, Social Security—to whatever marriages the states make.... 

More tactically, it would be terrible for Obama to talk about imposing same-sex marriage on states. The backlash would be horrifying—not just against same-sex marriage but against the imperiousness of the overeducated coastal elites. I get a little impatient with liberal straight folks who think that Doing The Right Thing is enough. I know I'm overcautious--I come from a different time--but there are still a lot of people who think it's disgusting to be queer, or even if they don't, just aren't there yet on opening marriage's doors. Those minds are more likely to open one at a time than if they feel their being dictated to by overeducated know-it-alls with no common sense. ... 

Law and culture change in tandem. The president's statement helps change the culture. ....The administration's actions are helping to change the law. If he gets re-elected, I believe we will see DOMA repealed before 2016, even with a Republican House.