“After several years of decline, the number of American children playing tackle football rose 2 percent in 2015, according to an analysis by USA Football. It’s hard to say how much of that can be attributed to the league’s marketing initiatives, but that’s more than 40,000 kids between the ages of 6 and 14 who have been persuaded to strap on a helmet in the middle of a health crisis we still don’t fully understand.”