CONSERVATIVES have decided that what ails America is that not enough of us are getting and staying married. They have a point. Not only are fewer people marrying than in the past but, more disturbingly, one out of every three children is born outside of marriage.  The life chances of these children are seriously compromised.  Far more of them will grow up in poverty, fail in school, and enter adolescence with a propensity to repeat their parents’ youthful mistakes. Indeed, as Jonathan Rauch has argued, and the data suggest, marriage is displacing both earnings and race as a source of division in America. Children growing up in a one-parent family are four times as likely to be poor as those growing up in a two-parent family, and those growing up in a single-parent white family are three times more likely to be poor than those growing up in a two-parent black family.