NOM disrespects my straight marriage
But when you look into their rationale for why they want to limit marriage, it becomes apparent that they're casting aspersions on many straight marriages as well. While NOM wouldn't try to stop me and my wife from getting hitched, their ideology disrespects the marriage we've formed.
NOM makes procreation central to their marriage discrimination rationale. M-F couples* are able to produce children through sex, and according to NOM a M-F couple provides the best environment in which to raise a child. The latter idea has been thoroughly debunked by every reliable study of same-sex parenting and is not supported by any major medical association.
That leaves us with the idea of procreative potential as the distinguishing feature. This part of NOM's rationale inevitably raises the question of why infertile M-F couples are allowed to get married. NOM attempts to address this in a recent post. I could actually accept it if their response was simply (as raised by some commenters) that it's a legal convenience, because verifying couples' fertility would be too expensive for too little payoff. But NOM wants to go further, making infertile M-F couples intrinsically suitable for marriage.
My wife and I are infertile. We're infertile by our own choice, and the assistance of an IUD (though we've never had any sort of testing done, so it's possible we may be infertile on other grounds as well). We're both in complete agreement that we do not want any children, ever. We are in agreement that we would make poor parents, and that raising children is not compatible with our desired vision for our lives. But since our sex still can involve a penis going into a vagina, and thus there's some tiny possibility that a pregnancy could result (or at least we're enacting a close simulation of the acts that can lead to pregnancy), we get to formalize our relationship with a legal marriage.
There are lots of things that I like about being married. I like the social recognition that it gives us. I like knowing that we have legal protections in the event that one of us becomes seriously hurt or killed. I like being able to put her on my health insurance. All of those things are important because we live together, we love each other, and we have intertwined our lives in significant ways. Our ability to do so would be threatened if society as a whole and the legal system in particular treated us as strangers.
And yet none of that is good enough for NOM. All of the ways that being married contributes to a stable family structure for us are not sufficient in their eyes. But yet the fact that our sex life looks like the kind of thing that could produce a baby somehow is. That feature of our relationship, a feature we are working our hardest to keep out of the picture, is what qualifies us for a NOM-approved marriage.
Therefore, I submit that NOM's view of marriage cheapens and disrespects my M-F marriage. NOM is attacking my marriage even while claiming to defend it from some alleged threat from same-sex couples.
*I don't like the term "opposite sex" because the idea that men and women are opposites is part of the same ideology that leads to marriage discrimination.