“And the star-spangled banner in triumph shall wave o’er the land of the free and the home of the brave”. The words of America’s national anthem, uplifting as they may be, do what all anthems do: they reassure a nation of its own self-image. That image is now being contested by another that asks who really is free, who really is brave and who really is at home in Trump’s America.

Memo to Trump after his NFL rant: sport is, and always has been, political Read more

The challenge comes from the image of American football players kneeling in protest during the anthem before matches. Their “taking a knee” action has fired the imagination and spread beyond football to baseball and even the world of showbiz, with Stevie Wonder among many stars seen following suit in solidarity. I don’t pretend for one minute to understand American football though I have been to several matches. It looks like rugby with crash helmets. But what I do know is a powerful symbol when I see one.

It started last year with Colin Kaepernick, then a player for the San Francisco 49ers, who knelt rather than stood during the anthem as a protest against police brutality. This sparked a conversation about race and the Black Lives Matter movement, for which Kaepernick sacrificed his career. He has, however, ignited a visible resistance that is spreading.

While there has been endless arguing on the US left about whether Bernie Sanders could have won the White House or whether Hillary Clinton was either too much of a woman or not enough of one to get elected, opposition to Trump still feels like a diffused and disbelieving rage.

Powerful symbols help focus that rage and “taking a knee” is now that symbol.

Kaepernick did something both brave and free. Trump is slapping down the footballers who have joined Kaepernick’s protest partly as a distraction, just as so much of what he does is done to distract (Kushner’s emails, obliterating North Korea, “bad ratings”). But this time the distraction is not working. Because the pictures speak a thousand more words than his deranged tweets. Kneeling rather than standing before the national anthem is a superb and poignant gesture that cannot be perceived as aggressive. Indeed it suggests humility and respect. Team owners, fans, white players see this. The rest of the world watches young men bow down, humble in their strength, united in their desire for change. This is not a pose of disrespect. It is the opposite.

What Trump represents on the other hand is not patriotism but white power. This is why he admires Putin, is supported by David Duke and refuses to condemn white supremacist violence. As Ta-Nahesi Coates wrote in his magisterial essay The First White President, “To Trump, whiteness is neither notional nor symbolic, but is the very core of his power. In this Trump is not singular. But whereas his forebears carried whiteness like an ancestral talisman, Trump cracked the glowing amulet open, releasing its eldritch energies.”

When Trump calls for the owners of football teams to discipline their players for speaking out, you wonder if he considers these athletes as nothing more than items of property.

In taking a knee the sports stars are defying both Trump and the idea that a discussion about race is unpatriotic. They are fighting for America, and they may be kneeling but they are standing on the shoulders of giants. It is not they who are disrespecting their country, they are hoping for a better one.

• Suzanne Moore is a Guardian columnist