Our former assistant editor Ryan T. Anderson writes in National Review Online that the solution to the marriage debate is not to privatize marriage because marriage is not just a religious issue. Instead, supporters of measures like Proposition 8 are looking to maintain marriage as the best, and therefore privileged, means of bearing and rearing children in society:
So if supporters of Proposition 8 aren’t seeking special protection for sectarian religious views, what do they want? Simply put, to preserve a sound understanding of marriage, for the well-being of both spouses and the children their union may produce. As Prop 8 supporters see it, the institution of marriage exists to bring a man and a woman together in a sexual relationship that is publicly recognized and approved because of its unique aptness for the bearing and rearing of children. Marriage attaches a father to his childrenand to his children’s motherand fulfills the societal need for children to have the love and care of both mother and father. This institution is the natural response to human sexual embodiment as male and female, to human longing for bonding and intimacy, and to human dependency and need (especially in view of the fact that human newborns, unlike newborns of many other species, require many years of nurture before reaching self-sufficiency). That is why a well-ordered society protects and encourages marriage in the first place.
That’s the heart of the argument, but I recommend reading the whole thing .