San Francisco 49ers safety Eric Reid and quarterback Colin Kaepernick kneel during the national anthem before a 2016 game. (Marcio Jose Sanchez/AP)

This is the problem.

A dark four-door Mercedes was parked across two spaces designated for the handicapped in an empty parking lot at 2 o’clock in the morning in front of a 24-hour Walgreens. A Milwaukee police officer noticed the car, approached it in his cruiser and stepped out to investigate.

Seconds later, a tall, young black man exited the store and approached the parked car, apparently his. The officer, white, approached the black man and said, “How you doing? You got a driver’s license?”

According to City of Milwaukee Parking Services Code 759, what the officer witnessed was unauthorized parking in a handicapped zone, for which the penalty is a $200 ticket.

But what the white officer did that cold Milwaukee night last January was berate the black man and call for backup officers, a gang of whom wrestled the black man to the ground and Tasered, handcuffed and arrested him.

The arrested man turned out to be Sterling Brown, employed as a basketball player for the Milwaukee Bucks. But that’s trivia.

The significance was Brown’s encounter as a black man with police, which resulted in him being manhandled for no reason. He wasn’t armed. He wasn’t threatening. Still he suffered the police brutality that we as black men bear disproportionately in this country.

What happened to Brown was what incited NFL quarterback Colin Kaepernick almost two years ago to start protesting by sitting and kneeling during the national anthem, which cost Kaepernick his NFL job.

But NFL owners would have you believe that black players with the audacity to pick up where Kaepernick left off are the problem.

Protesting during the national anthem is not the problem.

What induced protest during the national anthem is the problem.

It is that we as black men are more than twice as likely to suffer utter disrespect at the hands of police than are white men, which includes verbal threats (as were spat at Brown), restraining (as was done to Brown), subduing (as Brown suffered) or violence (as Brown suffered, too).

Yet, on Wednesday, as Milwaukee officials apologized for how Brown was mistreated while releasing a police bodycam video proving it, NFL Commissioner Roger Goodell, who is white like almost all of the owners who employ him, announced that players who can’t bring themselves to stand at attention for the national anthem must remain off the field or be fined should they demonstrate on it.

Not once did Goodell acknowledge the reason any of the league’s players, upward of 70 percent of whom are black, felt a need to protest at all. The players’ union even said afterward that the commissioner and owners didn’t even afford it the decency of consultation on an issue that would carry punitive consequences for its members.

The players’ union vowed it would challenge the league’s unilateral action. I hope it is in a court of law where it can remind Goodell, recalcitrant owners such as Houston’s Bob McNair and President Trump — whom Goodell et al. appeared to parrot — that the Supreme Court ruled in 1943 that one of our freedoms is we cannot be forced to pledge. As Justice Robert Jackson opined for the majority: “No official, high or petty, can prescribe what shall be orthodox in politics, nationalism, religion, or other matters of opinion, or force citizens to confess by word or act their faith therein.” NFL owners shouldn’t be able to take $7 billion in public funds to build their stadiums over the past two decades and disregard a fundamental constitutional protection.

What the league did Wednesday was add insult to injury that black men too often suffer encountering police. A lot of it, as Brown found, is just disrespectful. Some of it, as would-be NFL player Desmond Marrow found last December in Henry County, Ga., is sadistic. Marrow was body-slammed and choked — to unconsciousness, he said — by police after they investigated him for a verbal spat with another driver. The offending officer was fired this month.

The worst encounters we have with police are, of course, inhumane, as was 18-year-old Michael Brown’s meeting with a patrolman while walking down a suburban St. Louis street, unarmed, in the summer of 2014. He was shot to death by that officer, who suspected him of shoplifting.

It was that killing that brought Black Lives Matter, this century’s civil rights movement, to national prominence and first stirred black NFL players — five St. Louis Rams — to use their game as a platform to protest police brutality and lethality that seemed to have been unleashed with impunity against our ilk.

The NFL indicated Wednesday, however, that the life-and-death concern of the majority of its laborers is of no concern to it. Instead, the NFL showed it is most concerned about fans and sponsors who don’t want to be confronted with the realities of those they want to score touchdowns, make big tackles and carry their teams to the playoffs — in flesh or in fantasy. So the league stooped Wednesday to muzzle free speech, to camouflage dissent with a pretense of unity.

It is as if the league ignores each black player like Ralph Ellison’s Invisible Man, “Like the bodiless heads you see sometimes in circus sideshows . . . they see only my surroundings, themselves or figments of their imagination, indeed, everything and anything except me.”

For one weekend last season, the players refused to be dismissed. When Trump called them “sons of bitches” and championed the idea of NFL owners kicking them out of the league if they dared protest more, a couple hundred responded with remonstration. But they made the mistake of doing so with the very owners who decided Wednesday to punish them should they do so again.

It’s time they re-up on their own. What is most important now is that they not allow their moral fight to be obfuscated by league theatrics. It became more incumbent than ever Wednesday for black players, and those who would ally with them, to amplify Kaepernick’s protest of police violence. Because it is what happened to Sterling Brown that remains the problem.

Kevin B. Blackistone, ESPN panelist and visiting professor at the Philip Merrill College of Journalism at the University of Maryland, writes sports commentary for The Post.