Fistful (and others),
It isn't that gays want the government to recognize their sexual relationship. They want the government to recognize their relationship REGARDLESS OF their orientation.
Marriage, in most cultures, has almost entirely been about two things: Paternity and Property. Paternity, because if you couldn't be 100% certain of a female's activities and wherabouts, you couldn't know the little squallers were your own. We scowl at and mock Muslims who make their women wear the
chador, but there are still large numbers of Americans who concern themselves over the presence and condition of a maidenhead. And Property, because what the woman could materially bring into the marriage became her husband's, and after his death, to his sons. The wife belonged to the husband; he could do with her as he wished.
The government's interest is not on paternity, but property-What's his, what's theirs, and what is due to the Government. And from that base, a great many other questions come up: inheritance, insurance, parental rights, etc. Every marriage is a form of incorporation, even if we choose not to think of it that way. On what sound business reason would you allow one incorporation but not the other? It can't be purely a procreative one, or my Grandma wouldn't have been allowed to remarry at the age of 70. Do childless couples have fewer rights than another couple with six? Or fewer rights than unmarried parents?
As for European populations shrinking, yes, childbearing is down, but another big factor in the argument is that many Euros are worried about the influx of "non-whites" who could hold a majority of votes soon if the locals don't embark on a breeding program soon. For a good part of American history, immigration has been a huge factor in the creation of new consumers, manufacturers, and taxpayers. I'm proud to say that a far lower numbers of Americans are consumed with notions of cultural (racial) purity than the Euros. But there still some who are afraid, aren't there?
And as to the questions of pedophilia and polygamy, there is the standard of harm. Adults are not to engage in sexual relations with minors because we do not deem children capable of making such complex decisions, nor are they strong enough or willful enough to adequately decline to participate. Interestingly though, while sexual relations between adults and minors of a certain age are illegal, the age of consent is often much lower when the minor is to be married. (Please correct me if I'm wrong, but I read that in Kansas a child as young as ten may be married with the parents' permission) As for polygamy, it would be hard to argue that wife and husband were in any sense equal, or had equal say into getting married in the first place. If we look at current-day examples, such as the Fundamental Church of Latter Day Saints (who the mainstream LDS church have condemned and claim no affiliation to), the prosecutions and charges were not on polygamy charges, but on statutory rape (13 and 14-year old "brides") and fraud (for not paying taxes and for "providing" for the family by blatantly ripping off the welfare system). Imagine a FLDS family that was self supported and whose participants were all of legal age, and it would never see a courthouse; I imagine there are more than a few such families out there, not attracting attention.
Even for those who here who say they are opposed to Feminism, the way you approach your future wife and how you treat her during marriage is very different than in your grandparent's day. I think there are many today who could maturely handle polymarriage.
The biggest objection is a moral one, and while a great many lawmakers may see it otherwise, it is not the function of government to decide morality. It decides laws and enforcement of them, laws which strive to "keep the peace and order", and deter disorder and harm. And even if thinking about two men kissing nauseates you, it is not causing the breakdown of society. I'm certain there a great many married, heterosexual couples whose intimate activities would put you off your feed, too (Jim and Tammy Bakker were ALWAYS an appetite suppressant for me :barf: ).
Besides, think of the effect on the economy: If 10% of the population is gay, and half of them want to get married, there would be a huge boost in new house sales and durable goods.
I'll stop there.