Healthy democracies have ample room for politics but leave a larger space for civil society and culture that unites more than divides. With the politicization of the National Football League and the national anthem, the Divided States of America are exhibiting a very unhealthy level of polarization and mistrust.

The progressive forces of identity politics started this poisoning of America’s favorite spectator sport last year by making a hero of Colin Kaepernick for refusing to stand for “The Star-Spangled Banner” before games....