William C. Duncan in National Review's The Corner blog:

The decision of the Obama administration to change sides in the litigation over the Defense of Marriage Act got lots of mainstream press attention. The recent decision of 15 states to proactively file a brief supporting the Defense of Marriage Act at the U.S. Supreme Court has not gotten the same attention. That’s too bad, because the states’ brief makes some important arguments.

The states point out that the decision the Court is being asked to review creates a legal standard out of whole cloth and that if the circuit court’s analysis were taken seriously, it would require not only the invalidation of DOMA but of every marriage law in the United States. This latter point is crucial. DOMA may be the specific target now, but the litigation over it (and the related litigation over Proposition 8 ) is, ultimately, about establishing a new constitutional approach to marriage laws (similar to the context specific standards that have arisen in order to protect the “right” to abortion) that could be used to mandate redefinition in every state.