Actually, the "redefining marriage" argument makes much more sense to me than the bullsh*t that Republicans spew on economic issues. It's rooted on the idea (which, sure, is stupid, but not logically inconsistent) that tradition is inherently good and that some things should just not be changed ever. The GOP economic rationale is based on the ideas (among others) that tax cuts will allow us to balance the budget, that government expenditure never creates jobs EXCEPT military expenses, and that individuals should not be "dependent on the government" but that Medicare is great.