Bob Barr on our side: a renowned adversary of the gay rights movement, Bob Barr is arguing against a federal constitutional amendment to ban gay marriage.

One of America's most determined foes of gay rights could become one of the cause's most important allies. Former Georgia congressman Bob Barr, who was the architect of the 1996 Defense of Marriage Act, is now one of the nation's loudest critics of a proposed federal constitutional amendment that would ban gay marriage. His argument: DOMA, which allows states to refuse to recognize gay marriages performed in other states, is sufficient. A constitutional amendment would only hurt the country, he says.

The Advocate spoke with Barr, now a consultant to the American Civil Liberties Union and other groups in their efforts to defeat the marriage amendment, from his office in Washington,

Why do you oppose the proposed amendment to ban same-sex marriage?

I hold the Constitution in highest regard and I don't like to see it trifled with. I'm a firm believer in federalism. Even though I'm not an advocate for same-sex marriage, I want the states to decide the issue.

Some gay marriage opponents argue that DOMA is too vulnerable to court challenges, especially after the Supreme Court struck down sodomy laws.

Do I think it could stand up to any challenge? You never know for sure. But I don't think Lawrence v. Texas would be sufficient grounds. The more interesting question is what do we do about marriages between American couples performed in Canada? Under normal circumtances, those marriages would be recognized in the U.S.

You don't sound so vociferous about gay marriage anymore. Where did all the fire and brimstone go?

I've always believed that the great magic of a federalist society is that states can come up with their own positions and attitudes. If people don't like the laws in one state, they can move to another.

But for a lot of people, it's not that easy to just get up and move across the country to achieve the same rights as everyone else.

You're right from a perspective of fairness and everybody being treated the same. But I think the founding fathers really saw the strength in diversity of opinion. That's why they gave the states so much leeway in making their own decisions. We might end up with a patchwork of laws across the country. Even though I don't endorse same-sex marriage, I'm willing to live with that.

You don't seem as angry at the prospect of gay marriage as you once did.

Maybe I'm a mellower guy as I age. You'd have to ask my wife. [Laughs] I'm not a supporter of same-sex marriage, not then and not now. But perhaps being concerned about the erosion of the right of privacy and civil liberties has sensitized me. Since 9/11 the threats have become very real. I have seen very bad things happen to individuals when the government wields too much power over them.

Why do you oppose same-sex marriage?

The fact is that [marriage] is the longest-standing social institution in existence. It is based on a social relationship between man and woman, which is unique. It can't be replicated by any other two individuals.

Surely you should have a better argument than "tradition." Lots of terrible injustices have been "traditional."

Men and women were made both differently and complementary. They were built for procreation, the basic building block of society. Matrimony has always drawn the sexes together in a way that's recognized as unique and positive.

So opposite-sex relationships are inherently superior to same-sex ones?

Does it mean that every married couple is happy? That every marriage produces successful children? Absolutely not. Does it mean that every same-sex couple is unhappy? No. I'm only saying that heterosexual relationships are the preferred social unit.