When a school learns that one of its alums has achieved great things, the institution will usually seek to promote those accomplishments. But there are exceptions. If it's discovered, for example, that the former student also happens to be a member of the Ku Klux Klan, or a neo-Nazi, or a convicted felon, then the school will naturally seek to downplay the connection — and to sever any explicit ties between them.

To this list of offenses — normally reserved only for bigots and criminals — we can now apparently add opposing same-sex marriage.

Consider the recent experience of Ryan T. Anderson.

A graduate of the Quaker Friends School of Baltimore, Anderson has achieved far more than most 33-year-olds. He completed his undergraduate education at Princeton and earned a Ph.D. from Notre Dame. He has been cited by a Supreme Court justice (Samuel A. Alito, Jr., in his dissent from the majority opinion in United States v. Windsor, which struck down parts of the Defense of Marriage Act). He was recently named the William E. Simon Senior Research Fellow in American Principles and Public Policy at the conservative Heritage Foundation. And last week he was profiled fairly and respectfully in The Washington Post. (Headline: "The right finds a fresh voice on same-sex marriage.")

No wonder someone thought it made sense to post a link to the profile on the school's website.

But then the predictable uproar began. Before long, head of school Matthew W. Micciche had taken down the link and published first a brief and then a lengthier apology for having posted it in the first place. (Both statements were subsequently deleted. The longer one is quoted in its entirety on Anderson's public Facebook page.)

In his longer apology, Micciche expressed "sincere regret" for his "lack of sensitivity" and the "anguish and confusion" and "pain" the link inflicted on members of the school community who thought the link implied that the school was standing behind Anderson's views. Of course this could have been rectified with the addition of a simple, one-sentence note clarifying that a link does not imply an endorsement. But Micciche obviously thought this was insufficient for someone whose beliefs "begin from an assumption of inequality and that argue for the denial of rights to an entire segment of the population based on their identity." The only acceptable thing to do with such a person is to cut ties completely.

It's important to be clear about what's at stake here. This isn't about politics or the law. Unlike the recent RFRA disputes in Indiana and Arkansas, it has nothing to do with religious freedom or state power. Anderson has no right to be celebrated on the website of his alma mater. The Friends School of Baltimore can likewise link to or remove a link to anyone it wants for whatever reason.

The controversy is nonetheless important because of what it tells us about the cultural endgame of the gay-rights movement. The reaction of those who raised objections to the link as well as the decision of the head of school to remove the link and offer an abject apology for posting it — both of these are depressing signs that liberal public opinion is evolving in the direction of theological certainties and illiberal forms of intolerance. These so-called liberals want Anderson to be shunned. Expelled from the community. Excommunicated from civilized life. Ostracized from the ranks of the decent.

That is something that should trouble all fair-minded Americans.

Just in case you were wondering, I don't agree with Anderson on most issues, and certainly not on gay marriage, which I have supported for years. I laid out some of my disagreements with him in a column written over two years ago, and I've since tussled with him on Twitter on more than one occasion.

But so what? I disagree with lots of public figures, writers, advocates, and intellectuals on a wide range of issues. (Don't we all?) And as the Post profile noted, Anderson is unfailingly civil in public debates. Although he's the target of constant insults and ad hominem abuse online, he invariably responds with patience and respect — certainly more than I could muster. Why should this person, who's so patently devoted to the reasonable exchange of arguments, be considered beyond the bounds of civilized discourse?

Because, we are told over and over and over again, opposing gay marriage is rank bigotry, morally equivalent to arguing that African Americans deserve to be treated as second-class citizens, and certainly no different than denying their right to marry members of other races. Treating Anderson and others on his side of the issue with civility is just as morally outrageous as seriously entertaining the arguments of an educated and polite champion of anti-miscegenation laws in the Jim Crow South. The gay rights movement and many liberals increasingly want this to become the default, accepted, commonsense view.

They must not be allowed to succeed.

One reason why is that many millions of people still hold contrary views. Another is that their arguments are not frivolous — and certainly not as frivolous as rationales that were once used to justify racial inequality. Arguments in favor of traditional marriage — rooted in claims about the natural sexual complementarity of men and women — are also far more deeply rooted in human civilization the world over, and Western civilization specifically, than arguments against miscegenation.

Anderson himself provides an accurate summary in a quote contained in the Post profile:

Every great thinker who has ever written about marriage, you never see a discussion of race… Whether it's Plato, Aristotle, or Cicero, whether it's the Jews, Christians, and Muslims, whether it's Augustine, Aquinas, Luther, Calvin, John Locke, Immanuel Kant, Muhammad, Gandhi — none of them talk about skin color; each and every one of them talk about sexual complementarity. [The Washington Post]

Versions of these traditionalist arguments were accepted by nearly every human being who's ever lived until a couple of decades ago — and (supposedly) Barack Obama and Hillary Clinton until just a few years ago. Like them, I've come to reject those arguments. But saying they now seem wrong is one thing. Relegating them to the category of the foulest prejudice is something else entirely. It's reckless to break so quickly with the past and jump so easily to moral condemnation.

But that's not the only reason to stand up for Anderson.

The people who would drive him into moral exile seem to be afflicted with an almost comically high sensitivity to offense. A school posting a link to a fair-minded profile of an alum on the other side of an issue, with no endorsement of it, caused people "pain" and "anguish"? You've got to be kidding.

Like the students on college campuses who prefer to run and hide from the "trauma" of being exposed to arguments they don't like, those who claim to be wounded by a link to a story about someone who disagrees with them sound an awful lot like crybabies.

By all means, fight for your rights. Work to win the public argument. But then accept that the world is a big place, not everyone agrees with you, and those on the other side have as much right to make their (losing) case as you do.

That's what a genuinely liberal society is supposed to be all about. Do those who favor gay marriage really want to win by stamping out dissent and driving into the wilderness every person who holds a contrary position?

Apparently many of them do.

Well, they can go ahead and try. I just hope it doesn't hurt their feelings too much when the rest of us call them out for behaving like petulant thugs.