Three years on, supporters of same sex marriage are closer than ever to victory. If there was ever a time to discuss gay marriage, that time is now.

Thanks to a string of recent developments, gay marriage is once again at the forefront of national debate. Last spring, Canadian courts ruled to grant gay couples most of the same rights and privileges as married ones. The Canadian decision was followed in this country by a Supreme Court ruling that struck down state laws prohibiting sodomy. And, last August, the Episcopal Church, flouting tradition, scripture and the wishes of a large minority of its rank and file, appointed its first openly gay bishop, Gene Robinson.

In the midst of all this activity, pressure has been mounting in some state legislatures and city halls to pass laws extending marriage benefits to gay couples. Vermont and Hawaii already have gay-friendly marriage laws on the books. Massachusetts recently joined them, followed, early this Spring, by San Francisco, where Mayor Gavin Newsom issued marriage licenses to over four thousand gay couples. The San Francisco marriages have since been struck down by the California State Supreme Court on technical grounds.

On reflection, it’s amazing that supporters of gay marriage have gotten this far. Set aside the hype with which the issue is usually presented and one is left with a surprisingly feeble argument for an imaginary right. The standard argument for gay marriage goes something like this: Heterosexual marriage is legal (true). In most states, homosexual marriage is not (also true). Therefore, gay marriage advocates conclude, the civil rights of gay Americans are being violated (false!).

Where to start? In the first place, homosexuals are not denied the right to marry — they are denied a right to marry other homosexuals, which is something else altogether. Next, the argument trades on the idea — superficially appealing but practically empty — that discrimination is by definition a bad and evil thing. Denying legal status to gay marriage does indeed involve discrimination — but it is discrimination of a perfectly legitimate kind. Finally and most crucially, the argument assumes what it is meant to prove: the rights of gays are being violated only if you already agree that one of their rights is to get married to a person of the same sex as themselves. But that, of course, is precisely what is at issue.

It’s as if proponents of gay marriage believe that saying you have a right, loud enough and often enough, gives you one. While this tactic may succeed in silencing some of their opponents, it falls miserably short of making the sort of case that needs to be made if a specifically “gay right” to marriage is to be recognized. If gays hope to show that they have a right to marry one another, they will have to prove that they meet the same conditions that give heterosexual couples this right.

There’s no way around it: any discussion of gay marriage must begin with a discussion of marriage in general.

So why is heterosexual marriage recognized as a right? There turns out to be a very good reason for this. Married couples enjoy legal status and the benefits that go along with it (tax exemptions, automatic inheritance, joint pension status, insurance breaks, etc.) because our society long ago judged that the nuclear family raises children better than anyone else. Does the nuclear family always do a good job of raising its children? No. Are children always worse off with, say, single mothers? Obviously not. In general and with all exceptions excepted, however, it is broadly recognized that the nuclear family provides children with a more stable and nurturing environment than do alternate arrangements.

In other words, the right of marriage is inseparable from a public interest in the well-being of the family. By extending legal recognition and benefits to married heterosexuals, the government is merely seeking to protect and encourage that institution which, more so than any other, is responsible for the welfare of our nation’s young.

For advocates of gay marriage, this is all very inconvenient. After all, homosexual couples don’t typically do any of these things. They don’t have children; they don’t raise children; they don’t, as such, constitute a family unit with legitimate claims on legal recognition or public funds.

In short, the case for a right to gay marriage fails the test. For all the reasons that heterosexual couples enjoy a right to marry, homosexual couples do not.

Yes, yes, I know. Some married couples don’t have children. Some lesbians do. A few homosexuals — a very few — adopt. The law, however, aims at the general case, which in this instance means that it aims to encourage marriage as that institution best suited for child rearing. While it is unfortunate that many children are not raised in traditional settings, that fact does not in the least diminish the case for privileging the two-parent heterosexual family. Much less is it a reason to encourage the multiplication of “alternative” family structures. Quite the contrary.

But the feebleness of the argument for a right to gay marriage is not the only — nor even the most important — reason for opposing it. In addition to granting a right where none exists, the legalization of gay marriage would throw into doubt the future of the family itself. In the first place, homosexual couples are notoriously non-monogamous. Even if some homosexuals choose to settle down once married, there is abundant reason for believing that most will not. If so, there is a distinct danger that their example will weaken taboos on adultery within heterosexual families.

As Stanley Kurtz so eloquently wrote in National Review Online:

The libertarian asks, Just because two married gay men live next door, is that going to make me leave my wife? In a way, the answer is ‘Yes.’ For one thing, as a new generation grows up exposed to gay couples who openly define their marriages in non-monogamous terms, the concept of marriage will gradually change. No doubt, movies and television in a post-gay-marriage world will be filled with stories of the ‘cutting edge’ understandings of open marriage being pioneered by the new gay couples, even if the actual number of such married gay couples is relatively small.

Adultery is already a leading cause of divorce. Once gay marriage is legal, however, you can count on a vocal segment of the gay “community” celebrating adultery as part of a larger, radical critique of the traditional family. And it doesn’t take much imagination to realize what this will mean for the sexual morality upon which the husband and wife bond depends.

But an invitation to adultery is not the only way in which the example of married homosexuals will weaken and diminish the traditional family. Whatever else it is, gay marriage is a symbol of legitimacy. By insisting on a right to gay marriage, homosexual activists seek to put gay relationships on equal footing with heterosexual ones.

And that’s just the problem. Marriage is deeply embedded in our culture and institutions. For that reason, getting married is never a strictly private act: it depends on inherited roles, assumptions and values that are inseparable from the community in which it takes place. In particular, marriage depends on received understandings of the husband-wife relation and all that these entail for the distribution of authority within the family.

By elevating the same sex couple to the privileged status that has until now been uniquely reserved for the husband and wife pair, the idea of gay marriage directly conflicts with this tradition-oriented conception of marriage. If men can marry men and women marry women, there will no longer seem to be any reason for favoring a particular model of married life.

And this, of course, is exactly what gay-rights activists desire. As Richard Goldstein put it in a column for the Village Voice :

You’ll see leather weddings, boi-on-boi unions between queers of the opposite sex, trans matches that defy the boundaries of gender — all in cahoots with rice-throwing, trip-to-Niagara realness. Queers won’t stop being queer just because they can get hitched. The tradition of open relationships won’t cease to exist, nor will the boundless exploration of identity and desire. Marriage won’t change gay people, but merely affirm them as they are.

This may all be very well for radical activists intent on bringing about their chosen utopia of boundless choice and unfettered promiscuity. But it raises one very worrisome question: in a world where couples are freed from the expectations and traditions of community, what happens to the family?

No doubt we shall all be much freer under the new dispensation. Indeed, that’s just what worries me. Freedom can be a terrible thing.