I kinda/sorta agree but not really with Michael Kinsley: Opposing Gay Marriage in and of itself doesn't make you a bigot or a homophobe. That said, there are opponents out there of Gay Marriage who have said some pretty bigoted, homophobic things. I think there are also folks out there who are on that side of the issue for simple political or career reasons. In some parts of the country, it's still possible to demagogue that issue to get people to donate to your cause or vote your way or listen to your talk show, etc.
This is in addition to all the folks who oppose Gay Marriage just because it's a "win" for The Other Side. We've long since reached the point in this country where Republicans don't need any more reason to oppose something other than that Obama and/or Democrats want it. Last year at WonderCon, I found myself in a brief, pointless debate with a fellow writer over Global Warming. He thought it was an enormous hoax and his "evidence" wasn't science or temperatures or climate history. It was that Al Gore believes in it and to this guy, Al Gore is such a reprehensible human being that if he said it was Saturday, that alone would be undeniable proof it wasn't Saturday. There are Democrats who are the same way about issues that the Republican party supports or things Dick Cheney says.
Kinsley doesn't think Ben Carson should have been disinvited from speaking at Johns Hopkins Medical School. I don't think those kinds of things matter much but the First Amendment does not enshrine a right to express your opinion anywhere you want. It means the government can't shut you up. One could even argue that the deciders at John Hopkins have their own, equal First Amendment right to express their disapproval of Dr. Carson's position the way they did.
But I do agree with Kinsley that people these days are way too quick to play The Outrage Card. And I agree that proponents of Gay Marriage ought to be more gracious in victory than some are. And I agree that clinging to the old definition of "marriage" doesn't make one a monster. And I agree that we'll see the day when admitting to have once opposed Same-Sex Wedlock will be like admitting to a long-ago membership in The Klan…and when we get to that point, let's all be gracious about that. We all change our minds about things that we once felt strongly about. Or at least, we should.