No, you obviously don't: I view ceding the ability to define 'marriage' to the Federal Government as a loss, not as a protection.
Given the the PRISM project's blatant and flagrant disregard for the 4th Amendment, the 6th Amendment (FISA court), and arguably the 1st & 5th Amendment (incriminating yourself via any communications [read associations] you have), do you really think giving the ability to define marriage to the government via law is a good idea?
and I recognize that gay marriage and polygamy will happen as long as there is enough momentum on your side.
See, there's your problem: I recognize the proper place to spend effort protecting marriage as in the people's hearts. If you want marriage to mean something, then you have to act like it means something: lead by example, not yelling at others to do what you say.
HuH? Give America gay marriage and polygamy today, and win the people’s hearts tomorrow?
If conservatives win, we preserve marriage in America, if you win, then marriage is whatever any individual or religion, or atheist gay church, or Muslim Mosque wants to make of it.