To understand opposition to SSM, you must credit that it isn't about gays; it's about the institution of marriage, which is the foundation of our civilization. Advocates demand: "How does permitting gays and lesbians to get married hurt your marriage?"
It's the wrong question. Forty years ago, when illegitimacy was picking up steam in the U.S., conservatives expressed alarm. Liberals responded that traditional families weren't important -- that the only thing that mattered to children was love. Those who argued that the stigmas against divorce and unwed childbearing served important social functions were dismissed as Victorians or bigots. To decry the rise of illegitimacy was to be accused of insensitivity.
That experiment with alternative family structures didn't go well -- as all but the most benighted now acknowledge. The rate of illegitimate births in the U.S. is now 51 percent for women between 20 and 30. It's a slow-motion disaster for children, for parents and for the nation.
So how can those who value marriage object to offering its stability to a group that wants to marry? It's a reasonable question. What we do know is that changing the definition of marriage from a lifelong, exclusive commitment between husbands and wives to an expression of feeling between two adults has not gone well, feelings being mercurial. Enshrining SSM furthers that redefinition.
It may be that when SSM is widely available, same-sex couples will adopt exactly the same standards about commitment and parenthood that male/female couples practice (and, despite the alarming statistics, most still do). But it's also possible that gays will bring to marriage very different expectations. Andrew Sullivan, one of the fathers of the SSM movement, has noted that gay unions are more "open" and "flexible" than straight ones. If that's true, and surveys suggest that it is, will that affect the likelihood that married gay couples will stay together? We don't know. Will it adversely affect any children in the home? Again, unknown.
Nor do we know whether purposely denying to children of same-sex couples a parent of each sex is damaging. Does having two fathers erase the need for a mother or vice versa? It's too early in the history of this experiment to know.
What we do know is that traditional families featuring the lifelong, exclusive commitment of husband and wife are best for children and for society. Gays and lesbians are not responsible for the mess that our culture has made of family life. But perhaps they can understand that resisting its further redefinition is not bigotry but prudence.