I will attempt to keep this as unbiased as possible. I appreciate that you have presented an argument that is significantly more cogent than most that I've heard on the matter.
> Marriage is not a natural right, so first of all, no one has a "right" to marry. From the context of a debate about legalization of marital relationships, it's a privilege and a certification given by the government to a couple because the government feels there is a special social interest served by awarding that privilege and status to certain groups.
I agree with you that marriage is not a "right". I however do not think that there is a "special social interest" to be gained by awarding that privileged to heterosexual pairings and not to homosexual pairings. You address children later, and I will get back to that. However, I didn't see any other argument for what social good heterosexual relationships serve that can't also be said for homosexual ones.
>...there are important differences between the nature of these pairings, regardless of anyone's opinion on the morality of homosexual activity.
Outside of the natural born children question, I don't see any important differences.
> One is that homosexuality is considered immoral by large swaths of the population, and that official sanction and promotion of homosexual pairing will anger this significant segment.
Popular opinion is hardly a reason for whether or not one should or should not support something. Just look back a few decades at the civil rights movement. Interracial marriage. Desegregation of schools and public buildings. These are all things that once angered large swaths of the population. Do you think that the United States was in the wrong for supporting these things, just because it angered some people? Furthermore, popular opinion is shifting towards supporting gay marriage. Would you change your mind and support it if more people stopped supporting it? Do you vote with the majority on every single political decision? (I realize that this is an absurd question. In my opinion though, this is an absurd argument)
>If the most vital privileges can be granted with a "lesser" legal status, and we can strike a reasonable compromise that promotes peace and civil discourse, isn't that better than choosing the more divisive, incendiary method?
No. It isn't. It is spitting in the face of millions of people and telling them that they are lesser beings because of what other happen to think of them.
> I think that the debate is actually more about validation; homosexuals demand the government grant them and their relationships equal standing and promotion as it grants heterosexual relationships.
I think the debate is about equality. I have yet to see an argument on why homosexual relationships do not deserve equal standing.
> There are many other implications that flow from state equivocation of hetero and homo pairings.
Please do not invoke a slippery slope argument. It is weak and it is a logical fallacy. The role of churches is another debate that is not germane to the topic at hand.
> Does the community really have an interest in equalizing homosexual and heterosexual couples, when homosexual marriage cannot produce any children in the first place by its very nature, and when any adopted children are automatically disadvantaged without even the prospect of opposite-sex parental role models (a "mommy" and a "daddy")?
You make a large assumption here (that a lot of people make) that it is advantageous to have a "mommy" and a "daddy". I have yet to see anything but anecdotal evidence to back this claim up (that did not come out of obviously biased studies).
Furthermore, if that is your only "social benefit" that is to be gained by marriage (as I didn't see another one), and you believe that groups must prove that there must be a special social interest in getting this privelige to marry, then lets follow through. Lets take away the right to marry from senior citizens. From couples that are infertile. From couples that simply choose not to have children. I don't see any benefit to them being married.
> I understand that some people are eager to use the government to enforce their particular vision of equality on everyone else, and probably mean well, but that is not how a free society operates; you must convince people on your own merits, you don't just go and get the government to endorse your beliefs and then attempt to intimidate otherwise unwilling participants with that endorsement.
We do not live in an anarchy. We have a government for a reason, and one of the large reasons is to protect minorities. Unless there is a strong reason not to, our government should treat all citizens equally. That has been the stance the United States government has taken over and over again. And this time should be no different.
As far as "unwilling participants" go: What are they participating in? This is a decision that gives gay people a privilege. It doesn't take anything away from the majority of the population, nor does it force anything down their throats.