Well if you want talk factually, based in the US, the general population is more conservative then the rest of the world, and being as the majority of the population of America is Christian, I would say that the main reason for it not being legal is, that many are against gay marriages.
But if you want talk personally, I believe that as it is against the word of the Lord (in my opinion, interpret the bible in whatever way you want), then it would be a sin for two homosexuals to get married.
Again, I believe that if gay people wish to get married, let them do it. It's no skin of my nose, I just think it would be more appropriate in a civil union then acutal marriage.
I appreciate your straightforward owning that you think the majority should rule, without any protection for minority rights. In this case, we can simply agree to disagree. I know that I will never be able to convince you otherwise, but it is courageous of you to simply avow what many would deny, though it be pure sophistry.
For what it is worth, I disagree that the Bible condemns homosexuality at all, or that it is any more sinful than countless actions taken by the majority everyday including (using the same standard and appealing to the same authority, namely Paul) heterosexual marriage. I also fundamentally disagree that human rights are subject to vote, majority or otherwise. It is the ideal of US democracy, (seldom practiced, of course) that all humankind is created equally, and endowed by their creator with inalienable human rights.
Many have staked out the basic position here which I hold: I don't care if the basic right is for civil unions or marriage as long as the same standard applies to all. "Separate but equal" systems were long ago shown to be inherently unequal, however, and I can't agree with any proposal that thinks otherwise.
I, of course, think canon law should honor that principle the same as civil law, but God knows the church statutes in His name have long discriminated against women and minorities even while His scripture says they are beloved in His eyes. That will not be repaired in our lifetimes.