Saturday’s horrific attack on a Hanukkah celebration in Monsey, on the heels of multiple anti-Semitic incidents in Gotham last week and the recent carnage in Jersey City, is a wake-up call — even if leaders like Mayor de Blasio insist on sidestepping the grim realities.

The surge in attacks — at least eight in the city last week, before the Monsey assault — has Jewish communities scared, livid and demanding swift action.

De Blasio made a grand show of decrying the stabbings as a “tragedy” and rolled out new measures: more cops in Jewish areas, “neighborhood safety coalitions,” a greater focus on anti-Semitism in schools.

Yet even Monday, he was blurring the blame: “What we’re seeing,” he claimed, “is a horrible national crisis of anti-Semitism. We have to put this in perspective.” The city’s problems, in other words, are part of a national trend — driven by “an atmosphere of hate” created by . . . President Trump.

“The permission that’s being given for hate speech” — given by Trump, that is — “is underlying a lot of this.”

That’s absurd. Trump’s not OK’ing anti-Semitic hate; he has a Jewish daughter, son-in-law and grandkids and has been terrific for Israel. He could be stronger at times in condemning white supremacy, but that’s clearly not what’s driving the New York attacks.

Meanwhile, the mayor skirts over the true culprits, such as:

The city’s (and state’s) failure to address serious mental illness. A lawyer for alleged Monsey stabber Grafton Thomas says he has “a long history” of hospitalizations.

New York’s growing softness on crime. As The Post reported Saturday, the state’s new no-bail law will mean a quick get-out-of-jail-free card for all but one of the accused attackers in the eight anti-Jewish crimes in the city last week. Tiffany Harris is the rule, not the exception.

“You have to beat the hell out of somebody — or murder them — for there to be any consequences,” laments Dov Hikind of Americans Against Anti-Semitism.

Jew-hatred among some blacks, which de Blasio, Gov. Cuomo and other Democrats refuse to call out by name.

Some black leaders even promote anti-Semitism: Recall when City Councilwoman Laurie Cumbo blamed a spate of violent anti-Jewish attacks on black fear of being “pushed out” by Jewish landlords? She later apologized, but Jersey City school-board member Joan Terrell-Paige stands by her remarks, after the killings in her city this month, calling Jews “brutes” who “waved bags of money.”

The national Democratic Party itself has been increasingly open to anti-Semites: Bernie Sanders has embraced extremists like Linda Sarsour and Rep. Ilhan Omar. After Omar smeared Jews with her “It’s all about the Benjamins” quip, House Democrats shied from censuring her; Speaker Nancy Pelosi claimed Omar didn’t mean to be anti-Semitic.

And nearly every Democrat makes sure to kiss Al Sharpton’s ring, despite his role fanning flames during the anti-Jewish riot in Crown Heights.

De Blasio’s measures may help on the margins, but truly facing down anti-Semitism requires him to take a clear stand and admit the real sources of the hatred — as well as addressing the city’s growing failures when it comes to repeat offenders, including the seriously mentally ill.

Cuomo, too, needs to speak up, fix the no-bail law and push policies to get violent mentally ill people off the streets.

Even a letter from four Jewish pols — state Sen. Simcha Felder, Assemblyman Simcha Eichenstein and City Councilmen Chaim Deutsch and Kalman Yeger — seems meant more for show than serious action: They want Cuomo to declare a state of emergency, deploy the National Guard and State Police and appoint a special prosecutor. They, too, refrain from focusing on the core problem.

It’s beyond outrageous that, in a city with one of the world’s largest Jewish populations, politicians refuse to speak honestly about surging anti-Semitism. And when they avoid the right words, who can have any confidence in their actions?