I looked at Loughran v. Loughran. It is a 1934 SCOTUS case.
SCOTUS can easily overrule it.
I still believe amending the U.S. Constitution is the only way to preserve marriage in this nation.
Here's a snippet from
an informative document... (I just skimmed it, but it should help us figure all this out)
Despite the basic rule that a marriage valid where contracted is valid everywhere, the courts and validation statutes have universally recognized a number of exceptions, which may be condensed and simply stated as follows:
A marriage valid where contracted will nevertheless not be recognized as valid in the forum state if such recognition would be contrary to a strong public policy of the forum state. Restatement (Second) of Conflict of Laws 283(2) comment f (1971) (marriage valid where contracted will be recognized as valid everywhere unless it violates the strong public policy of another state which has the most significant relationship to the spouses of the marriage);
e.g., Fattibene v. Fattibene, 183 Conn. 433, 441 A.2d 3 (1981) (Connecticut need not recognize marriage that violates strong public policy of state);
In re Estate of Loughmiller, 229 Kan. 584, 629 P.2d 156 (1981) (listing exceptions to validation statute, including marriage that is polygamous, incestuous, or prohibited by the state for public policy reason);
K. v. K., 90 Misc. 2d 183, 393 N.Y.S.2d 534 (Fam. Ct. 1977) (court called upon to decide whether law of Poland, which requires civil ceremony in addition to religious ceremony, was repugnant to law of New York);
Kelderhaus v. Kelderhaus, 21 Va. App. 721, 467 S.E.2d 303 (1996) (general statement that marriage's validity is to be determined by law of state where marriage took place, unless result would be repugnant to Virginia public policy).
There's a lot more...
Anyway, I think we need to focus on the real weakness... Because of the above case law, I wouldn't expect the challenges to come based on FCC. But I wouldn't count on the "defined statute" clause to protect states who have them...
I'd expect the gays to challenge all the DOMAs, state and federal, saying they impede their favorite foggy federal rights - privacy and equal protection.
Avoiding that is why so many want the definitions codified in the US constitution via an amendment.