By Tom Watts* This is the fourth and final post in a series of blog posts previewing some of the conceptual questions that may appear in the same-sex marriage oral arguments on Tuesday. Part I is here, Part II is here, and Part III is here. In the previous three posts, I discussed the ways in which the Supreme Court might analyze the validity of the state same-sex marriage bans under the Equal Protection Clause of the Fourteenth Amendment. The plaintiffs also argue that the bans violate …