The editors at the National Review have come out in favor of the following constitutional amendment on gay marriage being sponsored by Orrin Hatch:
"Civil marriage shall be defined in each state by the legislature or the citizens thereof. Nothing in this Constitution shall be construed to require that marriage or its benefits be extended to any union other than that of a man and a woman."
Am I wrong in thinking that such an amendment would overrule Loving v. Virginia, the 1967 Supreme Court case that overturned state bans on interracial marriage? The second sentence ("Nothing in this Constitution shall be construed to require that marriage or its benefits be extended to any union other than that of a man and a woman.") is clearly intended to prevent courts from using the equal protection clause of the 14th Amendment to strike down gay marriage bans. But the first sentence ("Civil marriage shall be defined in each state by the legislature or the citizens thereof.") is much broader. Say, for example that the state legislature in Alabama decides to reimpose its ban on interracial marriage. Under this amendment, courts would have not constitutional basis for striking down such a ban since state legislatures are given unlimited power in this area.
I can think of two objections to this reasoning. Some would say that the second sentence, in addition to the first, shows that the authors of the amendment intended only to allow legislatures to bar gay marriage. But that seems a thin reed since, as conservatives have long pointed out, courts have a habit of reading things in or out of the Constitution.
Other would say that in this day and age, it's impossible that a state legislature or the people of a state would ban interracial marriage. Perhaps, but in 2000, Alabama held a statewide referendum to remove the ban on interracial marriage in their state constitution. This ban was, of course, null and void because of Loving but the referendum carried only by a margin of 60%-40% and 50% of white Alabamans still voted against the repeal (the data for this conclusion are forthcoming in a paper I'm writing). Given these figures, I'm not so sanguine about the impossibility of a state banning interracial marriage.