Fourteen months ago, President Barack Obama was a bigot. Now he is simply wrong. That's what you have to believe to agree with Justice Anthony M. Kennedy's majority opinion for the Supreme Court on the Defense of Marriage Act.

Kennedy writes that the only reason Congress had for passing DOMA - which defined marriage as the union of one man and one woman for the purposes of federal law - was to "disparage," "injure," "degrade," "demean" and "humiliate" gay and lesbian Americans.

So in 2008 when the American people elected a president opposed to redefining marriage, they elected a bigot. Got it?

When President Obama "evolved" on the issue just over a year ago, he insisted that the debate about marriage was legitimate one. He said there are people of goodwill on both sides.

Supporters of marriage as we've always understood it (a male-female union) "are not coming at it from a mean-spirited perspective," Obama explained. "They're coming at it because they care about families." And "a bunch of 'em are friends of mine," he added. "… you know, people who I deeply respect."

But by Kennedy's reasoning, Obama is wrong to express such goodwill toward those who disagree with him. In enacting DOMA, 342 members of the House, 85 members of the Senate and President Bill Clinton all must have been motivated by malice - or, to use the term Kennedy favors, "animus."

Obama is right, though. And so is Chief Justice John G. Roberts Jr. in his dissenting opinion, writing: "I would not tar the political branches with bigotry."

Kennedy's words highlight a larger cultural dynamic: The principal strategy of the forces that have worked for 20 years to redefine marriage to include same-sex unions has been cultural intimidation - bullying others by threatening the stigma of being "haters" and "bigots."

Marriage re-definers don't tend to say what many opponents have said, that this is a difficult question on which reasonable people of goodwill can disagree. No, they've said anyone who disagrees with them is the equivalent of a racist. They've sent a clear message: If you stand up for marriage, we will, with the help of our friends in the media, demonize and marginalize you.

This kind of grotesque incivility is toxic for any democratic community. And the fact that it has found its way into a majority opinion of the Supreme Court is not only outrageous but frightening.

We can do better.

Those in the media, for starters, can live up to their repeated claims to objectivity and nonpartisanship by providing fair opportunities for marriage advocates to make their case against those seeking to redefine marriage.

Marriage advocates need to learn how to state their case succinctly and winsomely: Marriage is how societies from time immemorial have united a man and woman as husband and wife, to be mother and father to any children born of their union.

Those in favor of redefining marriage have a role to play, too: Refuse to participate in campaigns of intimidation. Reject the strategy of demonizing opponents. Call out friends when they bully those who stand up for the historic understanding of marriage.

Then there's a role for all who agree with President Obama that Americans on both sides are good people worthy of respect.

We need to work to ensure that the government or anyone who receives taxpayers' money is prohibited from discriminating in employment, licensing, accreditation or contracting against those who believe marriage is the union of a man and a woman.

Christian adoption agencies already have been forced out of serving children because they believe orphans deserve a mom and a dad. Forcing out these agencies doesn't help those orphans, and it doesn't help our society. We need as many adoption agencies as possible.

The debate over the meaning and purpose of marriage will continue. We should conduct it in a civil manner. Bullies may win for a while, but theirs is a scorched-earth policy. They poison democratic discourse and fray the bonds on which democracy itself ultimately depends.

Even those who disagree with each other about morally charged issues of public policy need to be able to live together.

- Ryan T. Anderson is the William E. Simon Fellow in Religion and a Free Society at The Heritage Foundation and co-author, with Sherig Gigis and Robert George, of the book "What Is Marriage? Man and Woman: A Defense."