Gotham has faced another tragic loss: Police Officer Didarul Islam was the first victim in a Midtown office shooting on Monday.

The shooter, Shane Tamura, killed three more and wounded a fourth before taking his own life.

Officer Islam, though off duty, was doing what police officers do: protecting lives by risking their own.

Islam, aged 36, was serving as a security guard, but was dressed in his uniform that day. The uniform makes every officer a potential target, as they stand as the first defense for the public.

Tamura saw the blue and took the officer out, first thing.

Relatives and neighbors describe Islam, a father of two with his wife expecting their third, as a pillar of his community.

A friend said he joined the force despite the risks, because “he wanted to leave behind a legacy for his family, something they could be proud of.”

He certainly accomplished that.

But none of that heroism matters to the lefties who insist on smearing cops as racist villains.

Thus, it was telling that Zohran Mamdani’s response to the incident on Monday virtually ignored Didarul Islam, despite the mayoral candidate’s recent attempts to soften his historically anti-police stance.

Vacationing back on the family estate in Uganda, Mamdani tweeted he was “heartbroken to learn of the horrific shooting” and “holding the victims, their families, and the NYPD officer in critical condition in my thoughts” (though Islam’s death had already been reported) and finished with “Grateful for all of our first responders on the ground.”

That hardly squares with Mamdani’s record: “We don’t need an investigation to know that the NYPD is racist, anti-queer & a major threat to public safety,” he tweeted in 2020; “there is no negotiating with an institution this wicked & corrupt. Defund it. Dismantle it.”

When a social-media post mocked a crying police officer, Mamdani retweeted it, adding, “nature is healing.”

He’s been a leading cop-defamer, over and over demanding police, a face of “white supremacy,” be “defunded.”

Was Didarul Islam, a Bangladeshi immigrant said to be a religious Muslim, a “white supremacist” or “racist”?

Or more like “a true-blue New Yorker,” as Mayor Eric Adams put it, who gave his life in the service of others?

Fine: Mamdani these days has dropped the “defund” demands and even eventually posted a tribute to Officer Islam.

But he’s yet to fully disavow his anti-cop barbs.

And rather than rebuild the force’s ranks, as the other candidates vow, he’d disband the NYPD’s Strategic Response Group, which raced to the scene Monday.

His big “anti-crime” idea is spending $1.1 billion essentially on new social workers.

Most New Yorkers are mourning the loss of a true public servant and appreciating anew the enormous sacrifices police make to protect them.

Zohran Mamdani doesn’t deserve to be counted among them.