Why is it not simply in the state's interest to promote strong and stable families — regardless of whether those families contain children?
If there are children, then so much the better, as more individuals are protected by the stability of marriage. But that protection doesn't count as nothing for childless families.
The simple matter is that, undercurrent law, the ability to marry does not hinge on the ability or desire to have biological children. Indeed, seven states make it a requirement that certain couples CANNOT be able to procreate if they are to be allowed to marry.
Even leaving that aside, nationally, 35% of gay couples are caring for children. If, under your definition, marriage is about the protection and nurturing of children, how is your stated interest served by denying marital protections to those families? We allow and even encourage gay couples to adopt, yet deny their families the protections of marriage. What kind of policy is that?
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