If you haven't already seen it, Ted Olson —former Solicitor General and current plaintiff's co-lead attorney in Perry v Schwarzenegger — wrote Newsweek's cover article called The Conservative Case for Gay Marriage.
Look, I don't particularly mind his rehashing of all the usual "sweet mystery of life" arguments, but unfortunately, he omitted the fact that for the purposes of this constitutional case, marriage is fundamentally a beneficial legal status.My involvement in this case has generated a certain degree of consternation among conservatives. How could a politically active, lifelong Republican, a veteran of the Ronald Reagan and George W. Bush administrations, challenge the "traditional" definition of marriage and press for an "activist" interpretation of the Constitution to create another "new" constitutional right?...Marriage requires thinking beyond one's own needs. It transforms two individuals into a union based on shared aspirations, and in doing so establishes a formal investment in the well-being of society. The fact that individuals who happen to be gay want to share in this vital social institution is evidence that conservative ideals enjoy widespread acceptance....The United States Supreme Court has repeatedly held that marriage is one of the most fundamental rights that we have as Americans under our Constitution. It is an expression of our desire to create a social partnership, to live and share life's joys and burdens with the person we love, and to form a lasting bond and a social identity. The Supreme Court has said that marriage is a part of the Constitution's protections of liberty, privacy, freedom of association, and spiritual identification. In short, the right to marry helps us to define ourselves and our place in a community....No matter what you think of homosexuality, it is a fact that gays and lesbians are members of our families, clubs, and workplaces. They are our doctors, our teachers, our soldiers (whether we admit it or not), and our friends. They yearn for acceptance, stable relationships, and success in their lives, just like the rest of us.
To understand why this point is fundamentally important, consider how various other legal statuses — as a citizen, a felon, a minor, or an enemy combatant — affects your fundamental legal rights. Not just your fundamental right to marry, but your fundament rights to vote, to have a trial, to work, to enter into contracts, to travel, to own a firearm, etc.
Legal status is purely binary; which is to say that you either are, or you are not. You either are, or you are not, legally a minor. There is no middle ground — you cannot be sorta a citizen or somewhat of a felon.
That is why all the half-measures like civil unions and the so-called "everything but marriage" laws are cynical bullshit. If your legal status is unmarried, the law will treat you like you're not married, because the intent of the state and federal law is to treat married people differently, and so they do.
So anyway, the central legal issue in Perry is whether laws that categorically deny a certain class of people a beneficial legal status are constitutional. To that end, I would actually de-emphasize the comparison of today's gay marriage bans to the historical interracial marriage bans, and make what I think is the better comparison to the old bastardy laws.
Bastardy laws divided children into two legal statuses; legitimate offspring (the beneficial legal status that inured all manner of benefits, particularly to males) and bastards (a legal status that encumbered the child with a multitude of legal disabilities, such as the denial of paternal financial support or inheritance, plus added social stigma that affected such things as employment prospects).
During the 1970s (yep, it really was that late*), SCOTUS finally reconsidered bastardy laws. It was argued that granting illegitimate children the identical beneficial legal status as legitimates would necessarily increase the number of illegitimate births. Perhaps they were correct, given that today 40% of all US-born children are born extramaritally.
But even if that correlation is direct, the question then becomes: does the Constitution allow for a segment of society's moral disapproval of some adult romantic decisions to be enshrined as laws that punish their children? SCOTUS thought not, and struck the laws as violative of the Equal Protection Clause of the Fourteenth Amendment.
I think this argument throws the "marriage defenders" arguments right back in their face. If marriage is about what is good for children, and if it's society's obligation to protect children, why defend marriage bans that punish certain families and children by denying them the beneficial legal status of marriage?
Frankly, I think it's a more difficult argument to dismiss than the narrow reading that Loving v Virginia really was just about race.
(* But not as late as some. Until 1983, Roman Catholic canon law referred to illegitimacy as a "defect of birth" that disqualified a person from being ordained unless special dispensation was granted.)