Just as authorities are scrambling after the terror bombings in Chelsea and across the river, settlement talks are coming to a head in the lawsuit over whether the NYPD can keep tabs on Muslim communities in New Jersey.

That’s where the accused bomber, Ahmad Khan Rahami, allegedly hatched his would-be murderous scheme. That’s where Rahami’s own father two years ago warned an over-taxed FBI that his son was a terrorist.

FBI agents, though, couldn’t find anything on the aspiring terrorist and didn’t bring him in. Two years later, we have 31 injured, and it’s only by the grace of God that no one was killed.

Has anything since 9/11 made more clear that on both sides of the river all of us, of all religions or none, need all hands on deck? And that this includes the intelligence services of the NYPD?

The case where this is coming to a head is known as Hassan v. City of New York. It was brought in 2012 by New Jersey Muslims who alleged that the NYPD surveillance had violated their civil rights.

They complained about a program launched in the wake of 9/11 by the police commissioner, Ray Kelly. He hired a CIA official, David Cohen, who built a program merging intelligence tradecraft with police techniques.

Officers from the city’s amazingly diverse police force mapped and kept tabs on neighborhoods in the city and beyond. (After all, the 1993 World Trade Center bombers were also Jersey-based.) Not to “target” law-abiding Muslims but to spot trouble before it was too late and to understand the neighborhoods where future terrorists might hide.

Then, in 2011, the Associated Press began an exposé (which won a Pulitzer prize) that charged the NYPD had gone too far. And, District Judge William J. Martini complained, alerted New Jersey Muslims about the surveillance they would then complain about.

No doubt the plaintiffs include some courageous Americans. The lead plaintiff, Syed Farhaj Hassan, to cite but one, is a veteran of the US Army reserves who spent 14 months in active duty in Iraq.

At the center of their complaint, though, is the allegation that those on whom the NYPD was keeping an eye were targeted “solely” because of their religion. Judge Martini didn’t buy that claim.

“The more likely explanation for the surveillance was a desire to locate budding terrorist conspiracies,” Martini wrote. “The most obvious reason for so concluding is that surveillance of the Muslim community began just after the attacks of Sept. 11, 2001.”

Had bigotry been the motive, the surveillance would have started before 9/11, Martini reasoned. I thought that the judge deserved the Pulitzer — for logic. He dismissed the case outright.

Martini, though, was overruled by the Third Circuit. It suggested that the program of the NYPD echoed the darkest chapters in history. “We have been down similar roads before,” the court condescended.

Incredibly, it cited transgressions against “Jewish-Americans during the Red Scare, African-Americans during the Civil Rights Movement, and Japanese-Americans during World War II.”

“Outrageous” is how Kelly described the comparison. At the time, I noted that, to pick one example, there were some — by no means all or even most, but some — Jews who did side with the Soviet Union.

Yet Jewish leaders worked with authorities to root out the communists in their community. The Jewish labor movement was particularly courageous on this historic struggle.

Ignoring this, the circuit judges wondered “why we cannot see with foresight what we see so clearly with hindsight — that ‘[l]oyalty is a matter of the heart and mind[,] not race, creed, or color.’ ”

If so, whose case are the appeals judges making? If loyalty is a matter of the heart, does that mean the NYPD can’t keep an eye out for terrorists who might be hiding among the vast majority of Muslims who are loyal?

Neither New York nor Mr. Kelly nor The Finest nor the Muslim community deserved such insults. What they deserve is for the NYPD to be keeping its eyes and ears peeled for trouble.

Yet in January, the city settled two separate lawsuits over its surveillance in the Muslim communities. They don’t completely tie its hands, though, and the settlement talks in the New Jersey case take on a new importance.

The latest attack reminds us of the importance of the city standing its ground, in the hope that the NYPD can stay on maximum alert against another attack. It could, after all, be a lot worse than this one was.

This column first appeared in the New York Post.