When I was 16, my friends turned on me. I felt them gradually excluding me over several months, but the real break came the day a half-dozen of my buddies gang-tackled me, rammed me through a hedge, and fell on top of me. As I fought furiously to get them off me, I saw in their eyes that my pain and rage was the whole point, and that my new status as scapegoat had been discussed and planned. I didn'’t know why, but there were more tacklings and humiliations, and then one night, a mob of them tied me to a telephone pole far from home and left me wriggling there. I got it through my head that night that these were no longer my friends, and that was the last I saw or heard from them. I simply stopped going where they went, and found some safety and solace in my exile. This, of course, was all before bullies and mindless sadism could follow you home, and climb right out of your computer screen or cell phone.

I have two teenagers now, and have seen firsthand how dramatically social media have changed the experience of adolescence. It is hardly all bad: Facebook, texting, et al., can serve as a kind of warm cocoon, enveloping young people in the constant attention of their peers. Social media are no more inherently good or evil than a gun or a car or any other piece of technology. They simply amplify and extend what is already in our hearts—our hunger for connection, our perverse capacity for cruelty. Still, I am glad I am not 16 today.

—William Falk