Surely no one is actually pondering this question — “Why is violent crime surging in many cities?” — but that’s the title of a new article on The Crime Report website, a usually reliable compendium of crime coverage.

The answer, of course, is that respect for the police and for the Rule of Law has eroded in recent months. Sometimes it has been the fault of race-baiting political opportunists, and sometimes it has been the fault of a few bad cops. But there’s no mystery here. The windows are broken; lawlessness creeps in.

“A rise in homicides and shootings in cities including New York, Los Angeles, Baltimore, St. Louis and Milwaukee has raised fears that the nation’s overall crime rates, which began dropping 20 years ago, could be on an upward trend,” the website explains. “In some cities, spikes in violence came after the August 2014 police killing of Michael Brown in Ferguson, Mo. That led some commentators, criminologists and, notably, the police chief in nearby St. Louis to point to the ‘Ferguson effect.’ That’s the argument that police, fearful of being disciplined or even indicted for misconduct, have pulled back on enforcement amid protests and fierce public criticism of law enforcement after several prominent incidents of police killings and other violence against civilians caught on tape over the past year.”

The “Ferguson Effect,” if that is the culprit, is being felt nationwide.

“In St. Louis, police reported last week that homicide totals climbed nearly 60 percent, to 93, in the first six months of 2015 compared with the same period last year,” the report reads. “At the same time, robbery rose about 40 percent and aggravated assaults about 18 percent. Only rape and arson declined … In Baltimore, the number of homicides through early July has soared to 155 from 105 by early July a year ago, with violence surging after riots, protests and backlash against police after the April 27 funeral of 25-year-old Freddie Gray, who died while in police custody. Six police officers face charges in the Gray case.”

What’s really going on here is a philosophical shift away from the “broken windows” theory of policing.

As Louis Anemone, a former NYPD chief wrote in the New York Times recently, “‘Broken windows’ gives local commanders the discretion to crack down on minor offenses based on the complaints and practices of their communities. This enforcement often results in reduction and suppression of more serious crime.”

This approach worked, under then-Mayor Rudy Giuliani. But later administrations began to back away from it, saying the practice led to racial profiling and other abuses.

But abuse is not use — medicines can be deadly if misused, life-saving if used properly. Practices can be improved without abandoning policies.

The legitimate and historically successful broken windows approach is being lost as more and more departments are feeling political heat. They’re backing off, and lawlessness is filling the void.

There’s no mystery here. Violent crime is surging in many cities because activists and opportunistic politicians are demanding the police retreat. What did they think would happen?