Brave attempt, J.I. to get a reasonable discussion going - and Stevendedalus is one of the 'liberals' here!
Two completely separate things are being conflated here: the contract of marriage (a concern of the state) and the 'sanctity' of marriage (a religious idea).
The state has no more right to withhold recognition of marriage to same sex couples than it did withholding voting rights from women and black people. This is much more clearly understood in Europe and Canada (and is even being discussed in Asia!!!), but Americans still seem to be a bit more uptight about it, so expect to see gay marriage recognised in Cambodia before it is fully implemented in the USA. (Seriously; the former King has been arguing in favour of it there). Arguments about polygamy, incest and marrying horses are irrelevant. Some people argued that giving the vote to women would automatically lead to votes for children too. The problem with the 'slippery slope' argument is that it falsely posits that any change fatally undermines our ability to draw the line.
As to a religious definition of marriage - and its 'sanctity', that is a matter for individual churches and religions to decide on. No church should be 'forced' to conduct gay marriages that it strongly disagrees with for scriptural, traditional or theological reasons. Happily, no one is really suggesting that they be so. Religious affiliation is voluntary - if you join (or remain in) a religious body, you accept its rules; membership of the state is not.
As to those uptight enough to be irked by having gay sexuality 'thrust in their faces' (I imagine this is a reference to OTT carnival floats at gay pride parades; otherwise it could simply be irritation at any gay visibility at all), there is help on the way...
... I have argued before, but its worth saying again, all the best arguments for gay marriage are conservative. More convincing than any left-wing 'equality' argument, is the fact that, allowed to live lives of shameless hedonism and irresponsibility, once legal and social constraints were finally loosened, many gay men and women have discovered an essential emptiness in endless clubbing, partying and promiscuity. Instead they seek authentic relationships, commitment and fidelity. Of course if you are 'born again', you know that the answer is for these poor people to pray to Jesus to make them straight, but here on Planet Earth, where we realise that homosexuality is not simply going to go away, we need another strategy...
... prison, assault, mockery, social ostracism and the hangman's rope didin't really work. The brighter conservatives (including David Cameron, the new Tory leader in the UK) have concluded that making gays 'respectable' is the way to go. Gay couples with mortgages, rose covered cottages, and white picket fences, going to bed at 10 pm after a mug of cocoa, will only help to strengthen a traditional lifestyle (including faithful monogamous marriage) which many heterosexuals are abandoning .
To return to the "they thrust their sexuality in our faces" argument, the fact of the matter is that it is sexuality in general that is thrust in our faces in most western societies, and to choose to only get upset about one form of it speaks volumes.
