Sunday, professor Louis Henry Gates retreated from his threat to sue Sgt. James Crowley. Friday, President Obama retreated from his charge that the Cambridge cops “acted stupidly.”

As Crowley has not budged an inch—his arrest of Gates was correct, and there will be no apology—there is no doubt who won this face-off. Game, set, match, Crowley and the Cambridge cops.

It is, indeed, as Obama said Friday, a “teachable moment.”

And those most in need of teaching are the professor, the governor of Massachusetts and President Obama. By charging or suggesting Gates was a victim of racial profiling, all three were guilty of having reflexively reverted to racial stereotypes about white cops.

Here is the chronology.

Answering a 911 call about a break-in in progress, Crowley encountered the professor inside the house. According to Crowley’s report, his request for Gates’ I.D. was initially rebuffed, and he was accused of hassling Gates because he was black. The professor made a slurring reference to Crowley’s “mama.”

The professor then raised such a ruckus Crowley arrested and cuffed him.

Once in the street, Gates bellowed, “This is what happens to a black man in America.” Gates then called Crowley a “rogue cop.”

Gov. Deval Patrick declared Gates’ arrest “every black man’s nightmare.” Obama said the Cambridge cops had “acted stupidly” and went on to elaborate, on nationwide TV, on the sad history of racial profiling of blacks and Hispanics by police.

Thus the two most powerful black elected officials in the U.S., with no hard knowledge of what happened, came down on the side of a black professor, their buddy, against a white cop and his department, implying racial motivation in the arrest of Gates.

Yet there is still not a shred of evidence for their rush to judgment.

Crowley’s partner in the arrest was a black officer who said he stands “100 percent” behind Crowley and that Gates acted “strange.”

Sixteen years ago, Crowley gave CPR to an unconscious Boston Celtics star, Reggie Lewis, in an attempt to save his life. The memory of his failure caused Crowley to break down in tears and haunts him to this day.

Crowley was selected by a black police lieutenant to teach fellow officers about racial profiling. He has been doing this for five years.

And watching TV coverage for a week, this writer has yet to hear one cop anywhere condemn Crowley’s handling of the incident.

Outside the fevered imagination of Louis Henry Gates, then, where is the evidence Crowley engaged in racial profiling?

The victim here is Sgt. Crowley, not professor Gates.

Crowley is the one defamed as a “racist” and “rogue cop.” He is the officer whom Gov. Patrick implied perpetrated “every black man’s nightmare.” He is the cop on the Cambridge force who, Obama told the nation, “acted stupidly.”

If anyone has grounds for legal action, it is Crowley. Indeed, upon what grounds would Gates sue?

That he was wrongly arrested, when Crowley, his black partner, the Cambridge P.D., the police union and 1,000 cops would gladly come to Cambridge to testify that Crowley went by the book?

Moreover, no one says Crowley abused Gates in any way. And there were witnesses in the street to the arrest. And Crowley apparently had his mike open, and a recording of the incident exists.

But if Obama’s racial reflexes served him badly Wednesday night, his political instincts served him well him on Friday. For he must have sensed that this confrontation was shaping up as three powerful black men coming down hard on a white cop with a stellar record who had only done his conscientious duty.

Obama picked up the phone, called Crowley, regretted his choice of words about him and the Cambridge P.D., walked into the press room and told the nation Crowley was a “good guy,” he himself had misspoken, that he and the sergeant had talked about getting together for a beer.

It was a goodly slice of humble pie the president ate there, but it was a class act. To ask more would be churlish. As for Patrick and Gates, they, too, should eat a little crow.

The president’s decision to go before the White House press corps also suggests Obama is acutely aware of the political peril here.

For while his black support is rock solid, his white support is soft. And Americans will usually side with an Irish cop over a Harvard don, especially when the professor is pulling rank and the cop is right.

“This isn’t about me,” says Gates. Sorry, professor, it is about you. You have shown the country why William F. Buckley won laughter all over America when he wittily observed that, rather than be governed by the Harvard faculty, he would prefer to be governed by the first 300 names in the Cambridge telephone directory.