The justices of the U.S. Supreme Court meet on Monday to consider whether they should tackle the issue of same-sex marriage this term or give the lower courts more time to grapple with the question and flesh out the legal theories involved. What is perhaps most interesting about the evolution of this issue is that to date all the courts addressing the question have missed one remarkably simple proposition: Bans against same-sex marriage are unconstitutional as a matter of law because they punish children in an effort to control the conduct of adults.