THE AUTHOR of Sex and Unisex begins by quoting Republican candidate Rick Santorum from 2008: “You’re a liberal or a conservative in America if you think the ’60s were a good thing or not. If the ‘60s was a good thing, you’re left. If you think it was a bad thing, you’re right.” Jo B. Paoletti takes up this proposition by analyzing the clothing, hairstyles, and fashionable body types of the 1960s and early ’70s.