U.S. athletes Tommie Smith, center, and John Carlos raise their fists during the playing of "The Star-Spangled Banner.” (Anonymous)

Lonnie Bunch is the director of the National Museum of African American History and Culture. David Skorton is the secretary of the Smithsonian Institution.

An athlete silently protests during the national anthem. People respond with taunts of "traitor," "you're a disgrace" and "leave our country!" Are these angry tweets aimed at National Football League players kneeling during the national anthem? Or heated rhetoric about National Basketball Association players not visiting the White House? No, it is invective that was hurled at Toni Smith, the then-21-year-old senior guard on the Manhattanville College women's basketball team, who expressed her opposition to the Iraq War in 2003 by turning her back on the flag.

The history of protest in sports, much like that across society, holds many lessons for us that we can apply to the rancor that currently engulfs the nation. Sport has always been a canvas used to challenge convention, prove the worthiness of a marginalized group and prod the nation to live up to its stated ideals.

From John Carlos and Tommie Smith raising their fists atop the podium at the 1968 Mexico City Olympics to Colin Kaepernick taking a knee to highlight police brutality, dissent is as much a part of sports as it is a part of our democratic tradition. Athletes have used their fame as a platform to address injustice: Billie Jean King advocated for Title IX to bring about more gender equality in college athletics; the Phoenix Suns wore Spanish-language versions of their jerseys to protest racial-profiling laws; Muhammad Ali refused to participate in the Vietnam War.

If we are to move past reactionary anger, we must acknowledge the fact that the American experience differs among people and groups. Nothing brings that home quite like seeing a display of Jackie Robinson, a hero for breaking the Major League Baseball color barrier, and finding out that he, too, saw the flag in a different light due to the racism he faced every day. As he wrote in his 1972 autobiography: "I cannot stand and sing the anthem. I cannot salute the flag; I know that I am a black man in a white world."

Robinson and many other athletes have played critical roles in enabling social change that has created a more inclusive society, often at great risk to their careers. Any suggestion that athletes should “stick to sports” diminishes their courage and ignores the deeply held tradition of dissent that separates liberal democracies from authoritarian states.

Our nation has always struggled to equally apply the ideals embodied in our Constitution and the Bill of Rights. Although the United States is steeped in the principles of individual liberty, freedom of expression and democracy, people of color, immigrants and women have struggled to receive the full benefits of citizenship. And the struggle to perfect our union continues. Admitting to our imperfection is not a weakness, nor is it unpatriotic.

As Toni Smith said in a statement following the uproar over her protest: "It is my right as an American to stand for my beliefs the way others have done against me. Being patriotic cannot simply be an empty slogan. Patriotism can be shown in many ways, but those who choose to do so by saluting the flag should recognize that the American flag stands for individuality and freedom."

To many who profoundly love the United States, protest is one of the highest forms of patriotism. The need to "form a more perfect Union" is enshrined in the preamble to the Constitution. The framers knew that the only way to improve our democratic republic is to continuously assess it and work to make it better through principled dissent and vigorous debate, and that happens regardless of whether the debate emanates from the halls of Congress or a football stadium. Increasingly, though, many of us seem to be ignoring the lessons that history has to offer.

Museums and other cultural institutions are a potential solution for this. Sport is a powerful way to do so because it resonates with people; passion for a team is often passed down from generation to generation. When we display Tommie Smith’s warm-up suit and explain why he and Carlos raised their fists at the Olympics and the costs they incurred by doing so, generations of people who weren’t yet born can see both the progress made and the unfinished work ahead of us.

In some ways, sports are conducted on the ultimate level playing field, a meritocracy where ability outweighs backgrounds, beliefs, race and religion. Athletes have unique insight into working toward a goal and looking past individual glory for the greater good. As such, they have something profound to say about our nation, our freedoms and who we aspire to be. We should listen.