Gay Marriage... why the drama?

One of the most argued over issues in the 21st century is that of gay marriage. People debate the issue so fiercely that, dare I say it, froth begins to seep from their sputtering mouths. Conservatives are against it, particularly the religious right. Liberals are generally all for it. My question: why in the world is this such a definitive issue? It practically was the main topic during the 2004 Presidential election. I wonder this because I think it's a simple matter of human rights. I wonder this because there are more dire issues to be dealt with. I wonder this because I would like for humanity to move on.
I've come up with a theory as to why the religious right dislike homosexuals. Strong Christians do not approve of sex before marriage; in fact they (at least in public) believe that sex should only be reserved for procreation. Two men or two women cannot reproduce, and therefore their sex is, in the church's point-of-view, just good ol' promiscuity. It is to them a clear cut case of hedonism. That homosexuality is 99% of the time a genetic matter does not seem to compute with hardcore Christians. Then again, these are the same people who still ignore the reality of evolution. But when you have 1/10 of people being gay, you'd think that the general population would learn to be more accepting. Is it such a difficult concept to think that God loves his children equally, and doesn't give a damn about their sexuality? I think that in forty years we will look back upon this era with the same puzzlement and disappointment that we feel today when we recall segregation.
What is the problem here? That to grant homosexuals gay marriage would defy the sanctity of it? I think that sanctity was defiled already when the government turned marriage into a legal contract, complete with tax exemptions and all. What makes two people worthy of a marriage? Isn't that they are in love good enough? Apparently not so; apparently a dude and a chick who get married only to get bitterly divorced two years later are more worhy of marriage than, say, two men who want nothing more than to spend the rest of their lives together. This, I think, is obviously a matter of civil rights, only hindered by prejudice and the ignoring of God's message in favor of honoring rigid rhetoric of a time in the world where for someone to be different would be reason enough to burn them at the stake. I'm tired of this issue being argued over, and I want it resolved. Cooler heads should prevail, and then focus their energy on terorism, the economy, and genocide in Darfur.