Just after the first of the year, an NFL player named Damar Hamlin literally died on the field—he had a cardiac arrest as a result of a blow to the chest—and was resuscitated. That was still in the back of my mind when I noticed among my PDFs a New Yorker article by Malcolm Gladwell about football. I had saved it but for more than 10 years avoided it, fearing it would tell me something I didn’t want to know. I was right. It’s profoundly disturbing.

American football isn’t played everywher...