John Leo:

Two decades of research produced a consensus among social scientists of both left and right that family structure has a serious impact on children, even when controlling for income, race, and other variables. In other words, we are not talking about a problem of race but about a problem of family formation or, rather, the lack of it. The best outcomes for children--whether in academic performance, avoidance of crime and drugs, or financial and economic success--are almost invariably produced by married biological parents. The worst results are by never-married women.

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The upshot of these studies is that America is confronted by a form of poverty that money alone can't cure. Many of us think social breakdown is a result of racism and poverty. Yes, they are factors, but study after study shows that alterations in norms and values are at the heart of economic and behavioral troubles. That's why so much research boils down to the old rule: If you want to avoid poverty, finish high school, don't have kids in your teens, and get married.