I didn't realize how bad the NFL's concussion problem was until many of its players developed kneeling sickness during the singing of the national anthem. . The kneelers claim they are protesting racism, but kneeling is usually done as a form of submission, not a form of protest. In the NFL, a player who fields a kickoff in the end zone will kneel to show he doesn't plan to run with the ball. Late in the game the quarterback on the team that is leading will "take a knee" to run out the clock. Kneeling is what a slave may...