Not so long ago, American high-school students were educated in “sex hygiene.” They were told, “Save the conjugal act until marriage or you’ll get horrid diseases; if you’re a girl, you might become pregnant; and, boys, don’t marry an easy girl.” The lessons yielded low rates of STDs, illegitimacy, abortions, fatherless households, and welfare dependency. They saw high rates of virginity (even Hugh Hefner was a virgin in college) and social stability.