San Francisco 49ers quarterback Colin Kaepernick, left, and safety Eric Reid kneel during the national anthem before the 49ers game against the Dallas Cowboys in Santa Clara, Calif., on Oct. 2, 2016. (Marcio Jose Sanchez/AP)

John Feinstein is a Post contributor and author of “Next Man Up: A Year Behind the Lines in Today’s NFL.”

Here we go again.

A little more than a year ago, when Colin Kaepernick became a National Football League free agent after kneeling for the national anthem to protest white police brutality against African Americans, the 32 NFL teams insisted he didn’t get a job because he just wasn’t that good anymore.

Kaepernick started the last 11 games of the 2016 season in San Francisco but all of a sudden wasn’t good enough to serve as a backup. Teams signed quarterbacks from the Arena Football League, retired players, players who had never been starters — but not Kaepernick.

A year later, Eric Reid is the new Kaepernick. Reid, who was a starting safety for the 49ers the past five seasons, was the first player to join Kaepernick’s protest. Throughout last season, Reid continued to kneel. Of course, hundreds of NFL players kneeled during the season after President Trump profanely declared at a September rally that he wished NFL owners would respond to players kneeling by saying, “Get that son of a bitch off the field right now, out. He’s fired. He’s fired!”

Some players kneeled once, others more than that, and almost every team locked arms during the anthem to show their unity in the aftermath of Trump’s rant.

We are now two months into the offseason signing period for free agents. Most free agents who were starters last season had contracts before April. The exceptions were players near the end of their careers or those coming off major injuries.

Eric Reid is 26 and healthy. And unsigned.

Even before he became a free agent, Reid predicted this might happen. He has also said he is likely to stand for the anthem this season because “we understand you have to change with the times,” adding, “I’m not saying I’m going to stop being active, because I won’t. I’m just going to consider different ways to be active.”

It’s worth remembering that Kaepernick said last year he would stand for the anthem during the 2017 season because he felt he had accomplished his goal of raising awareness and opening a dialogue on the issue of police brutality.

No one signed him. It was, quite simply, punitive behavior brought down by a small group of rich, almost entirely white men on an African American who dared to step out of line.

But there’s a key difference between Kaepernick and Reid. There’s simply no way the owners can sell the myth that Reid’s not good enough to play. He would start for most teams. Last season, he played free safety, strong safety and even some linebacker for the 49ers.

So far, one team — the Cincinnati Bengals — has brought Reid in for a job interview. It didn’t go well. Bengals owner Mike Brown reportedly asked Reid if he could guarantee he wouldn’t continue to protest, and, when Reid said he couldn’t do that, the interview quickly ended.

Reid has filed a grievance accusing the owners of colluding to keep him from finding a job. The NFL Players Association has also filed a grievance, specific to the Bengals because there is no NFL rule against not standing for the anthem, which, to the union’s mind, made Brown’s question a violation of the collective bargaining agreement. The Bengals have refused to comment on what happened in the interview.

Proving collusion is virtually impossible without a smoking gun. What’s clear, however, is that the owners don’t need to actually collude. No coordination was required for them to simply decide, as a group, that Reid will be punished just as Kaepernick was.

They don’t want the president yelling that they’re anti-American because they aren’t “firing the SOBs.” They’re also aware that most of their season ticket-holders are white, and many of them booed loudly when players took a knee last season.

The owners believe the best public-relations play is to go along with the notion that not standing for the anthem is anti-American. They’re not that concerned that punishing someone for exercising First Amendment rights is far more anti-American.

Really, the owners would like to see the issue go away. By late last season, only a handful of players were not standing for the anthem. The smartest thing the owners could do is sign Reid somewhere without any caveats about not protesting. Any team that signs him will get a player who will make the team better and who isn’t likely to kneel during the anthem. And if he does, so what? A few fans will boo. Then the game will start.

In all likelihood, Reid won’t be signed. The owners will anonymously claim to various co-opted media members that he’s not the player he used to be — just as they did with Kaepernick. And the controversy will continue. As it should.

Being rich doesn’t mean you’re smart, honest or fair. It just means you’re rich.