I find it incredibly insulting to suggest that the NFL players who are taking a knee during the anthem are ignorant of the reason for their action. I doubt very much if either the president or a recent letter writer have ever bothered to listen to the players.
I have heard many of them articulate very well their reasons for taking this action. All you have to do is listen. The writer should also realize that the act of kneeling is a universal sign of respect (think knighthoods and marriage proposals). I wonder if those who have criticized the players for their respectful sign of protest will have the courage of their convictions and boycott the football season as they threaten to do. I doubt it.