It’s kickoff time for the NFL, starting with a Super Bowl rematch between Denver and Carolina on Thursday night, Sept. 9, and continuing at 1 p.m. Sunday, Sept. 11, when the Falcons start their final season in the Georgia Dome against the Buccaneers.

On that 15th anniversary of the most devastating terrorist attack on American soil, some football players will start the season by sitting through the national anthem. As explained by Colin Kaepernick, the backup San Francisco 49ers quarterback whose jersey has become a national best seller since he began this movement of standing up by sitting down, the protest reflects a refusal to show pride in a nation that oppresses blacks and other minorities.

Colin Kaepernick

Colin Kaepernick

By exercising a First Amendment right to speak up, sit down and protest, Kaepernick and a small number of other players are showing why the United States is a country worth expressing pride in, despite its flaws. Fortunately, a sense of irony is not a prerequisite for First Amendment rights.

The tradition of singing the national anthem and paying respects to the flag is not a statement of blind patriotism, but instead an expression of belief in the national ideals of liberty and justice. Again, Kaepernick and others are free to disagree.

The focus of the quarterback’s wrath is what motivated marches in Atlanta and across the country this summer: police killings of black people. We’re not clear what sign of reduced oppression Kaepernick seeks to end his protest; we suspect he doesn’t have a clear idea himself.

Most police do a good job, respond to the people they serve and protect based on those people’s actions, not their appearance, and rarely resort to lethal force. And black people are not the only victims of bad cops.

But it’s natural and understandable for black people to focus on the threat to their lives, just as it’s natural and understandable for supporters of Israel to break with the Black Lives Matter movement over one small portion of the Movement for Black Lives platform that takes gratuitous, false and offensive shots at Israel. After all, as Hillel said, while we have a responsibility to others, we first have to look out for ourselves.

And so we get the contradictions inherent in such a protest. A uniquely American, highly violent sport played by privileged men, many of them paid millions of dollars a year, becomes the venue for a uniquely American protest of American violence to gain more safety and security for Americans. The protest falls on the anniversary of a day that briefly united us in tragedy but has since led to our surrendering many of our American liberties in the hope of gaining safety and security.

Some people support that protest as the ultimate expression of American freedom even as others support it as the perfect exposure of the hypocrisy behind that freedom. Others are angry at Kaepernick for the political point he’s making or the venue he’s choosing.

He’s not the first athlete to use his celebrity as a political platform, and he won’t be the last. But we hope everyone respects the essence of the First Amendment principle involved here: Not only does Kaepernick have a right to protest, but each of us has a right to respond as we see fit. And we all benefit from encouraging the resulting free, respectful exchange of ideas rather than rejecting those whose views don’t perfectly align with our own.