Unless you've hurled your phone and your laptop into the ocean in a recent fit of frustration and rage (who could blame you? Not us), you've probably heard many of the attacks directed at San Francisco 49ers quarterback Colin Kaepernick, and his decision to sit during the raising of the American flag and singing of the national anthem. Many of these attacks are easily swatted away: the right to free expression is right there in the Constitution, growing up with white adoptive parents doesn't magic away one’s blackness, sports and politics are already inextricably mixed, etc.

But the arguments employed by some of Kaepernick’s defenders are themselves deeply flawed. I’m thinking in particular of those rallying to Kaepernick’s side on the grounds that the national anthem is simply a song, and the flag is just cloth — people who are offended by the protest are attaching unwarranted significance to both.

But to strip the flag of the symbolism it carries is also to sap the power of Kaepernick's protest. The flag is more than a piece of fabric — and that is precisely what gives meaning and significance to his refusal to venerate it.

The border separating protest and art is porous. Almost all protests have an element of symbolic performance. One device that sometimes distinguishes protest from "pure" art is the way protest relies on disruption and taking up space — occupying ground, blocking a road, interrupting a ceremony. (Some public artworks also incorporate disruption, of course, but it's no coincidence that these are often explicitly political.)

Kaepernick's decision to sit for the anthem did not rely on disruption. In fact, it was so unobtrusive that it wasn't even noticed the first time he did it. It relied on a symbolic act, one with enough room for interpretation that Kaepernick needed to spell out its meaning. His protest was a piece of performance art, and in staging it he blurred the line between art and protest. Kaepernick isn't just a part of the long line of black athletes who have used their platforms to speak out about political issues; he (unintentionally) inserted himself into the rich tradition of black artists who have invoked the American flag in political protest.

On October 16 1933, in Maryland, an elderly white woman reported an assault and an attempted rape, identifying her assailant as George Armwood, a black laborer who lived nearby. The police first found and beat Armwood, then arrested and jailed him. Two days later, a crowd of one thousand people laid siege to the jail, used battering rams to knock down its doors, then forced one of the deputies to give them the keys to the cells. They wrapped a noose around Armwood's neck and dragged him away behind a truck, then beat, stabbed, and hung him. Then they brought his corpse back into town, strung it up on a telephone pole in front of the courthouse, and burned it, in front of a crowd that had swelled to 5,000.

In response to the lynching, Esther Popel, a black poet associated with the Harlem Renaissance, wrote a poem entitled "Flag Salute." The poem alternates the lines of the Pledge of Allegiance with an account of the brutal murder of Armwood. This juxtaposition reframes the pledge, sardonically demonstrating how its high-minded rhetoric was actually being practiced in America.

One passage reading "(Three thousand strong, they were!)/'One Nation, Indivisible'—," presents the vision of a unified country as the lynch mob and those who had gathered to watch. The last stanza describes Armwood's teeth being put on gold necklace chains, bookending this description with "For ALL!" In doing so, Popel hangs Armwood's death around the necks of all of white America, pronouncing them complicit.

"Flag Salute" points out that the flag that represents the America of our perfected ideals also symbolizes the America of our imperfect reality. But Popel goes even further, pointing out that the apparent contradiction between what America is and what it claims to be is easily reconciled — once you define the terms. "ALL" applies only to white people, "justice" includes extrajudicial executions, and the cause that makes America "indivisible" is that of white supremacy.

The poem, which was published in the NAACP's magazine The Crisis, drew an unsurprisingly controversial reception. In 1936, the Board of Education for Washington, D.C., recommended that The Crisis be banned from public schools, and specifically cited "Flag Salute" as one of the reasons that the magazine was inappropriate. That Popel had employed the flag in order to address lynching was more offensive than the lynching itself. Though state police officers identified nine men who led the lynch mob, a local grand jury declined to indict any of them.

In 1964, California passed Proposition 14, which re-legalized housing discrimination, undoing the Rumford Fair Housing Act enacted just a year prior. This combined with the LAPD's reputation for police brutality led directly to the Watts Rebellion, an uprising in the solidly black Watts neighborhood of Los Angeles. It was around this time that David Hammons began work as an artist in the city. He gained attention with a series of works he created by covering himself with oil, pressing his body against a large piece of paper, and then sprinkling the canvas with pigment. The resulting ghostly afterimage — which he termed a body print — is reminiscent of a photocopy or airport body scan.

Occasionally, Hammons's body prints incorporated images of the American flag. In one instance, Black First, American Second, two men are presented in profile, back to back, with the lower halves of their bodies draped in a black-and-white American flag. The flag is tucked under their armpits, so that their arms rest on top, and it looks at first as if they are lying asleep, with the flag covering them like a blanket — were it not for the fact that one of their faces is contorted into an open-mouthed scream, and the other's neck is unnaturally swiveled so that his head is facing the opposite direction from the rest of his body.

The body printing flattens the figures into distorted two-dimensional images — here Hammons is making use of the fact that the word "stereotype" originally was used to describe a printmaking method — and so too are the identities of black Americans. In other contexts, the phrase "black first, American second" could read as defiant black separatism, but as the title of this piece, it represents black disenfranchisement. The "black" in "black American" serves as a qualifier that strips them of their American rights and inheritance as citizens.

Around the same time, on the opposite coast, Faith Ringgold was employing the flag in similar ways in her paintings. One of her works from this era, at first glance, presents as a painting of an ordinary American flag, if slightly off-hue — substituting a dim gray for the traditional white. But on closer examination, what appears to be some discoloration in the stars is the word "die," in capital letters only a shade darker than the field on which it is superimposed. And what appear to be irregular stripes are actually horizontal, elongated letters, which spell "nigger."

Made in 1969, the same year that the Apollo missions were beaming back the first images of men raising the American flag on the moon, Ringgold's Flag for the Moon: Die Nigger bluntly confronts America with the implications of its own budget priorities. The country had decided to spend vast sums of money on a demonstration of American superiority, while its black citizens languished in poverty, in a country where the promise of the Civil Rights Movement was only fulfilled on paper. For Ringgold, every tax dollar spent in space was evidence of the relative worthlessness of black lives in the eyes of their country. Ringgold's painting made explicit the fact that to black people, the sight of that flag erected on the moon didn't represent the promise and possibility of their American experience — it represented a threat. You can literally leave the planet and white supremacy will be there, waiting for you.

In the late 1980s, Dread Scott presented a controversial installation that consisted of a framed photomontage of protestors and coffins draped with American flags, with the header "What is the Proper Way to Display a US Flag?" Below the photomontage he mounted a shelf with a blank book in which those who wished to participate could write down their responses to the the question. And laid on the ground, directly in front of the frame and book, was a 3-by-5-foot American flag. This meant that if you wanted to look at the picture more closely, or write in the book, the most direct way to do so was to stand on it.

In What Is the Proper Way to Display a US Flag?, Scott demonstrated that it is much easier to confront America's injustices and participate in the project of building America into the country it should be if you do not see America as sacrosanct. After all, how can you fix what you don't think can be broken? How can you improve something that you believe is sacred? A sampling of responses written in the book sound like they've been pulled directly from the current debate. "If you don't like this country and you don't like our flag then get the hell out of here and go back home," reads one, sounding a lot like Donald Trump suggesting that Kaepernick "find another country." "The U.S. flag is a tool for continued oppression of People of Color throughout the world," reads another. Some responses claimed that Scott's artwork was disrespectful to the military, while others cited black American veterans who did not stand for the pledge of allegiance.

The tradition of invoking the flag in protest continues into the Black Lives Matter era. Last year, William Pope.L presented an updated version of his 2008 installation Trinket, an enormous and disproportionately long flag (54 by 16 feet), illuminated by giant klieg lights and set continuously waving by massive industrial fans — the kind used to create fake storms on movie sets. At the rightmost edge of the flag, the stripes are not completely sewn together, so that as the exhibition goes on, the end of the flag begins to fray and unravel from whipping back and forth, pulling apart the red from the white.

Trinket's hyperreal depiction of an America literally coming apart at the seams is powerful by itself, but it acquired new layers of meaning when Kendrick Lamar used it in the stage set of his performance at the 2015 BET Awards. Kendrick performed his pro-black protest anthem "Alright" atop a vandalized police cruiser, with Trinket as his backdrop. Even in the face of the shredded American social fabric, an economy "looking at me for the pay cut," and police that "wanna kill us dead in the street fo sho," Kendrick proclaimed a message of rebellious hope: "We gon' be alright." Kendrick Lamar's ragged Trinket, like Francis Scott Key's "Banner," is a flag of defiant survival.

Kendrick is able to write himself into the American flag for the same reason Kaepernick can write himself out of it — the American flag is a political object and its meaning is malleable and contestable. It is the banner of the federal government, and the battleflag of the American military, but it can carry other meanings that are just as potent. It is the symbol of the American dream, the American way, its values, its history, its principles, its traditions. But the flag isn't just a symbol of the America of our abstract ideals; it is one of the America that actually exists.