A pretty deep essay about the cosmological nature of the fight:
Too many of them think that same-sex marriage is merely a question of sexual ethics. They fail to see that gay marriage, and the concomitant collapse of marriage among poor and working-class heterosexuals, makes perfect sense given the autonomous individualism sacralized by modernity and embraced by contemporary culture—indeed, by many who call themselves Christians. They don’t grasp that Christianity, properly understood, is not a moralistic therapeutic adjunct to bourgeois individualism—a common response among American Christians, one denounced by Rieff in 2005 as “simply pathetic”—but is radically opposed to the cultural order (or disorder) that reigns today.
They are fighting the culture war moralistically, not cosmologically. They have not only lost the culture, but unless they understand the nature of the fight and change their strategy to fight cosmologically, within a few generations they may also lose their religion.