It is difficult to imagine that New York City mayor Bill de Blasio can continue governing after he has lost the confidence of the police department in such dramatic fashion.

On Saturday, police officers staged a silent protest by turning their backs on the mayor as he arrived for a press conference at Woodhull Hospital, where two New York Police Department officers, Rafael Ramos and Wenjian Liu, were brought after being assassinated in an act of revenge for alleged police brutality elsewhere.

De Blasio had stoked public outrage against police when he identified with nationwide protests against the non-indictment of white police officers in the deaths of black suspects. Earlier this month, a grand jury declined to indict a NYPD officer in the death of Eric Garner, an unarmed cigarette vendor who had been resisting arrest in Staten Island. Though there was no evidence of a racial motive in the case, de Blasio called the Garner death and others like it evidence of “centuries of racism.”

The mayor also offended police by relating that he had told his biracial son that police were a threat to him, supposedly due to racism. And though the mayor had insisted that protests remain non-violent, two police officers were recently beaten in a protest as it crossed the Brooklyn Bridge. The mayor then poured fuel on the fire by referring to the attack as “alleged,” though the event had been captured on video. Police representatives said the mayor would not be welcome at police funerals.

New York is ungovernable without an effective police force, which in turn requires the strong political support of the mayor. Former mayor Rudy Giuliani, who is credited with cleaning up the city in the 1990s, was steadfast in supporting the NYPD, even in controversial circumstances.

On Friday, Giuliana explicitly criticized De Blasio’s handling of recent anti-police protests, specifically his tolerance of the protestors’ habit of choosing whatever route they liked for their demonstration, regardless of the city’s needs. “When I met with protesters or when we were going to have a protest, I was always cognizant of the fact that I came into office after two major riots,” Giuliani said, according to the Wall Street Journal. “I decided riots ended in New York City, and they ended.”

(Update: Speaking to Fox News on Sunday morning, Giuliana added that “It goes too far to blame the mayor for the murder, or to ask for the mayor’s resignation,” saying that he felt De Blasio had not acted out of bad intentions.)

The recent anti-Blasio statements by police may be “wildly inflammatory,” as a Sunday editorial in the New York Daily News suggests. Yet they are clearly intended to send a signal that they reject his leadership.

The police in New York do not have, nor should they have, veto power over the elected, civilian leadership. Yet they have seen themselves reduced from heroes in the post-9/11 era to targets of public vilification. That is an impossible situation for a police force that must rely on public cooperation and trust to prevent and solve crimes. It is also an affront to a force that prides itself on professionalism and respect for the diverse, multicultural, international city that New York has become.

Part of the problem is the ideology that de Blasio has brought to office–and some of the characters, such as Al Sharpton, who has been accused of interfering in police affairs throughout de Blasio’s first year in office. “The mayor’s alliance with the racial provocateur is now creating the biggest crisis of his mayoralty,” wrote Heather MacDonald in the Wall Street Journal in October. De Blasio’s rejection of “stop-and-frisk” police tactics has also hamstrung the NYPD, and provoked resentment.

Absent a reconciliation between De Blasio and the NYPD–mediated, perhaps, by the clergy–New York will likely become more disorderly and divided. It is difficult to see what De Blasio can do to make amends. He ought to resign–not as an admission of fault, but to let the city heal and move forward.

Given that our politicians today are focused on winning rather than doing the right thing, De Blasio is unlikely to quit. But doing so would be the greatest public service he can render.

Senior Editor-at-Large Joel B. Pollak edits Breitbart California and is the author of the new ebook, Wacko Birds: The Fall (and Rise) of the Tea Party, available for Amazon Kindle.

Follow Joel on Twitter: @joelpollak