[quote=@Galaxy Raider]
Logic. It just seems incredibly illogical to me to use Christian-established rights and wrongs for people who don't even follow the Christian faith. This is especially so if you are trying to convert people, as people today are like stray dogs. You bring them in by being gentle, not by chasing them down, catching them, and throwing them in a cage.
[/quote]

I will use again the point that God punishes immorality. We, as Christians, know that God punishes immorality, and even if we're not trying to convert a person, we [i]do[/i] want them to still realise that what they do is wrong--or, at least, try not to do it. And what is the best way to prevent a person from doing wrong without converting them or convincing them? Make laws that punish wrongdoing. Therefore people will be discouraged from doing wrong, and if they still do wrong, then they will be punished, as would happen anyway.

Let me put it in a logical ladder:
God punishes immorality.
We do not wish for others to be punished.
If one does not want to be punished, then they should not be immoral.
If we do not want others to be punished, then we should discourage them from being immoral.
Laws that punish immorality discourage people from being immoral.
Therefore, if we do not want others to be punished for immorality, then we should put into place laws that punish immorality.
I can extend this argument to show that, despite the existence of other methods to discourage people from being immoral, this is an avenue we should take.