On today’s Fresh Air, sports journalist Howard Bryant. He is a senior writer for ESPN.com, and ESPN the Magazine. He's also a correspondent for NPR's Weekend Edition Saturday. His new book is The Heritage: Black Athletes, a Divided America, and the Politics of Patriotism. In light of the current debate over African-American athletes, like Colin Kaepernick, who refuse to stand for the national anthem, Bryant examines the long tradition of athlete-activism that goes back to Jackie Robinson, Bill Russell, Muhammed Ali and others. Interview by Dave Davies.