In an interview with the New Yorker's Jeffrey Toobin, President Obama now believes that same-sex couples in every state should be allowed to marry under the equal protection clause of the Constitution — a significant switch from his earlier stance in May 2012, when he believed the issue was best left to the states. Here's the relevant passage from Toobin's lengthy interview on how the president is planning to shape his "judicial legacy":

"Ultimately, I think the Equal Protection Clause does guarantee same-sex marriage in all fifty states," he said. "But, as you know, courts have always been strategic. There have been times where the stars were aligned and the Court, like a thunderbolt, issues a ruling like Brown v. Board of Education, but that's pretty rare. And, given the direction of society, for the Court to have allowed the process to play out the way it has may make the shift less controversial and more lasting."
"The bulk of my nominees, twenty years ago or even ten years ago, would have been considered very much centrists, well within the mainstream of American jurisprudence, not particularly fire-breathing or ideologically driven," Obama went on. "So the fact that now Democratic appointees and Republican appointees tend to vote differently on issues really has more to do with the shift in the Republican Party and in the nature of Republican-appointed jurists ... Democrats haven't moved from where they were."

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Why you should care: To some extent, Obama's support for gay marriage doesn't matter: The country has already evolved right past him and other prominent Democrats like Hillary Clinton. A GOP-controlled House (and possibly soon the Senate) means that any federal legislation on the topic is off the table for the next two years, while it's very unlikely the Roberts court will see any justices replaced before the end of Obama's second term.

But Obama openly backing the right of gay couples to marry — and laying out a constitutional justification for it — is still a major milestone for the gay rights movement. It will now be significantly harder for any potential successor to backtrack on gay marriage, and the support of the nation's leader will make Republican opposition to same-sex marriage look increasingly bigoted.

Coupled with his historic executive order protecting all federal contractors against LGBT discrimination, the president may still squeak out of this one with a progressive legacy. Had the nation not gotten over its homophobia so fast, we might still be waiting for the first openly pro-gay president.