Freedom has never been free.

It has always cost and it has always been white people who have decided what the cost would be.

For Fannie Lou Hamer, the civil rights activist who co-founded the Mississippi Freedom Democratic Party, the cost was permanent kidney damage, a blood clot in the artery of her left eye and a limp when she walked.

For Myrlie Evers and Coretta Scott King, it was the untimely deaths of their beloved spouses, Medgar Evers and the Rev. Martin Luther King Jr., at the hands of assassins.

Evers’ killer, Byron De La Beckwith, was a member of a white supremacist group. James Earl Ray, who assassinated King, was a drifter and a fugitive from the Missouri State Penitentiary and had to be extradited to the United States from London.

OPINION

Black Americans who dared speak out about racial injustice were lynched, bombed out of their homes, chased out of neighborhoods, fired from their jobs and were blatantly denied an opportunity to seek redress for these wrongs.

Still, there has always been at least one black person willing to take that risk.

In refusing to stand during the national anthem last season to protest police treatment of minorities, Colin Kaepernick, the former 49ers quarterback, became that person.

Like those before him, the athlete is paying a steep price for his activism.

Kaepernick’s career came to a screeching halt when he became a free agent. For the 2017 season, not one other NFL team opted to sign him. Not one.

It was an obvious punishment that sparked petitions and the public shaming of the NFL.

But a recent tirade by President Donald Trump has prompted a number of NFL players to pick up where Kaepernick left off, with some players deciding to take a knee during the national anthem or to link arms with teammates.

At a rally in Huntsville, Alabama, on Friday, Trump drew applause when he asked: “Wouldn’t you love to see one of these NFL owners, when somebody disrespects our flag, you’d say, ‘Get that son of a bitch off the field right now. Out! He’s fired.” On Sunday, at Soldier Field, the overwhelming majority of the Pittsburgh Steelers opted to stay in the locker room while the Bears linked arms.

Trump later tweeted: “If NFL fans refuse to go to games until players stop disrespecting our Flag & Country, you will see change take place fast. Fire or suspend.”

The president is pandering to the white people who don’t ask black people. They tell.

But the privileged class doesn’t get to tell the oppressed class how they should react to oppression.

Kaepernick’s silent protest brought attention to the police mistreatment of minorities, but Trump is trying to make this about the flag — a hot-button issue that always riles up white patriots.

It is not enough that these black players are getting their brains knocked out for entertainment. In Trump’s America, they owe a debt of gratitude to “flag and country” for the privilege.

Frankly, Trump is acting like the NFL owners are slave owners.

But Trump’s actions are likely to encourage more black players to join this crusade.

Because what Trump doesn’t get is this: When these black players take off their NFL uniforms and leave the stadium, they are considered n—— and they know it.

They also know that if they get pulled over by the wrong police officer, in the wrong neighborhood, they could end up as dead as Jason Stockley in St. Louis or Philando Castile in Minnesota.

Without a football in their hands, they face the same oppression that every other black man faces in this country.

So Trump can rave and rant as if his bluster really matters.

It doesn’t.

Those who take the knee know this isn’t a game.