Is confidence a cult? These sociologists think so.

It’s hard to pin down exactly when it happened, but if you paid attention to women’s media in the 2000s and kept paying attention into the next decade, you definitely noticed it. Magazines that devoted their pages to diet tips and celebrity snark suddenly started preaching “empowerment.” Fashion brands that made clothing that only went up to a size 12 wanted you to “love your body” just the way it was. Parenting books wanted you to know that messing up was okay, that as long as you raised resilient, self-assured...