Andrew Sullivan knows one when he sees one:

Some now want this president to be Andrew Cuomo, a heroically gifted advocate of marriage equality who used all his skills to make it the law in his state. But the truth is that a governor is integral to this issue in a way a president can never be. Civil marriage has always been a state matter in the US. That tradition goes all the way back; it was how the country managed to have a patchwok of varying laws on miscegenation for a century before Loving vs Virginia. The attack on this legal regime was made by Republicans who violated every conservative principle in the book when they passed DOMA, and seized federal control over the subject by refusing for the first time ever not to recognize possible legal civil marriages in a state like Hawaii or Massachusetts. Defending this tradition is not, as some would have it, a kind of de facto nod to racial segregation; it is a defense of the norm in US history. And by defending that norm, the Obama administration has a much stronger and more coherent case in knocking down DOMA than if it had echoed Clinton in declaring that the feds would dictate a national marriage strategy.

More to the point, until very recently, if we had had to resolve this issue at a federal level, marriage equality would have failed. The genius of federalism is that it allowed us to prove that marriage equality would not lead to catastrophe, that it has in fact coincided with a strengthening of straight marriage, that in many states now, the sky has not fallen. That is why a man like David Frum has changed his mind—for the right conservative reason. Because there is evidence that this is not a big deal and yet unleashes a new universe of equality and dignity and integration for a once-despised minority. Obama's defense of federalism in this instance is not a regressive throw-back; it is a pragmatic strategy.

The president has no actual political authority over this issue. He does have moral authority. But what close observers know about Obama is that he does not think of the presidency the way he thinks of a campaign. He knows he is president of all the people, including those who voted against him and those who conscientiously oppose marriage equality. He does not seek to divide as his predecessor did. By staying ever so slightly above on this issue, Obama is doing the right presidential thing—while presiding over what may well be the most seismic period for gay equality in history.