With all the talk about "marriage equality" and "defending traditional marriage" and "gay marriage" and all that stuff, I figured it was time for me to think the questions through and try to come up with a reasonable solution. Of course, what I've come up with is so simple and makes so much sense that it will most likely never even be considered by anyone else...
Let me preface this with some very basic information about me.
Spiritually, I am a Christian - my beliefs would probably fall under a category I'll call "semi-liberal protestant." With this said, however, do not make the assumption that anyone else who claims the title of Christian speaks for me. Specifically, neither the pope, nor the Roman church speak for me. Neither do Fred Phelps and his ilk. Neither does anyone who wishes to establish a Christian theocracy who isn't Jesus Himself. In fact, I specifically and vehemently reject most of what those people teach. My over-riding belief can be summarized in one verse from the new testament: "love the lord your God with all your heart, soul, and mind .. and love your neighbor as yourself" (Matthew 22:37-40). Specifically, I do not believe that Christianity is about giving up vices or practicing rituals - it's about loving God and loving people. And it certainly is not about hating people who aren't like me. "Now these three remain: faith, hope, and love - and the greatest of these is love" (I Corinthians 13:13). See that? Love is even greater than faith itself! Chew on that for a while...
Politically, I am a libertarian. What this means, basically, is that as long as I'm not hurting you, leave me the hell alone. I will leave you alone, and the government should leave us both alone. While I see the need for some laws and government, I believe that these should be limited to what is minimally necessary to ensure everyone's rights are secure. I really like the part of the US declaration of independence that says, "We hold these truths to be self-evident, that all men are created equal, that they are endowed by their Creator with certain unalienable Rights, that among these are Life, Liberty and the pursuit of Happiness.--That to secure these rights, Governments are instituted among Men, deriving their just powers from the consent of the governed .. " Government, therefore, is not intended to solve all of society's problems. Rather, it is to secure our God-given rights through liberty and rule of law.
What does all this mean in the context of the marriage question, then?
The fundamentalist wants to "defend marriage" through legislation enforced by the state. The liberal wants "marriage equality" enshrined in law and enforced by the state. Basically, both sides want their religious views (or lack thereof) to become the law of the land and to be forced on people who don't hold to them. Both sides, therefore, have it wrong. "Congress shall make no law respecting an establishment of religion, nor prohibiting the free exercise thereof .." (US Constitution, Amendment 1)
You see, at its core, marriage is a religious institution. Therefore, the government is not allowed to define what it means for anyone. What I am proposing here is simple religious freedom. Rather than pick and choose who's marriage is legitimate and who's isn't in the eyes of the state, I suggest that the state shouldn't be in the marriage business at all. Rather, let each person define what it means and practice their own religion without government sanction or interference. If a couple desires to give legal force to their marriage vows, let them negotiate, draft, and sign a contract enforceable under contract law.
This way, the government wouldn't be compelling anyone to violate their religious sensibilities by forcing them to recognize a marriage they see as invalid, and, conversely, anyone could marry whoever they want without the government saying they can't because of someone else's beliefs. We would all simply be free to live our lives the way we see fit. The only people who are going to be upset about that are those misguided "Christians" and other "believers" who want to force their beliefs on everyone else .. and as a Christian, I'm completely ok with pissing those people off as much as possible.