We celebrate Muhammad Ali not just for his talent, but for taking two seismic events -- civil rights and Vietnam -- and giving people the courage to find their voice about both. He was hated for it, and it cost him the best years of his career.

We celebrate John Carlos and Tommie Smith for raising their fists in Mexico City in 1968 as a protest against racial inequality, even though they were pilloried at the time.

We celebrate the greatest of our heroes, Jackie Robinson, even though he was despised by so many Americans -- to the extent that he would never salute the flag because he was "a black man in a white world."

Many other athletes now sanctified for their courage were told to zip it and play at one time or another, such as Jim Brown, Billie Jean King and Bill Russell. So it is hard to reconcile the cultural amnesia and the hostility being hurled at Colin Kaepernick.

The 49ers quarterback refused to stand during the anthem Friday, and whether you think he managed to revive a discussion about police conduct and racial injustice, his right to protest must still be applauded.

He did not use a bullhorn. He only spoke up after the media caught on: "This is bigger than football and it would be selfish on my part to look the other way," he explained. "There are bodies in the street."

Kaepernick in his own words.



Should he remain sitting during the National Anthem? VOTE: https://t.co/NvAGkVGxAupic.twitter.com/ueny2q5gMX — The Tylt (@TheTylt) August 30, 2016

Some will never understand that message, and fewer will approve of the actual boycott. But it was a seminal act of courage: Kaepernick took a stand, probably jeopardizing his career, and absorbed an avalanche of hate. A viral video even shows a fan burning the player's jersey as it hung from a tree while he sings the anthem. An interesting expression of American values, that.

Here's what is wrong with this picture: No one can deny that sports is a prism that shapes how we see ourselves as a country. So you cannot canonize Ali and vilify Kaepernick, whose impact cannot be felt nor measured in real time. But the day will come when we wonder why more people didn't have his courage.

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