T he more I listen to debates over whether we should promote marriage, the more I am reminded of one of my father's favorite sayings: "If wishes were horses, then beggars would ride." Yes, kids raised by married parents do better, on average, than kids raised in divorced- or single-parent homes. Yes, the long-term commitment of marriage confers economic, emotional, and even health benefits on adults as well. Certainly, we should remove marriage disincentives from government programs -- 16 states, for instance, still discriminate against married couples in welfare policy. We should expand health coverage to include "couples counseling" for all who wish it. With better support systems, we may be able to save more potentially healthy marriages and further reduce rates of unwed childbearing among teenagers. But there is no way to re-establish marriage as the main site of child rearing, dependent care, income pooling, or interpersonal commitments in the modern world. Any movement that sets...