Her parents started taking her to prayer vigils outside abortion centers when she was a child, and she witnessed firsthand the vitriol abortion supporters sometimes hurl at people pleading for the lives of unborn babies. But that didn’t make it any easier to face the same kind of ridicule and derision in her own high-school cafeteria.

Once, while handing out abortion information at Dripping Springs High School near Austin, Texas, Curran endured a harangue from a fellow student that included a stinging (though untrue) personal attack: She must be pro-life because she was sleeping around. ...