When they are aligned, as they were in New York City for many years, good things happen. When they are not, as now in New York City—Sacramento has not yet tried broken windows policing—bad things happen.

That is the subject of this story from City Journal.

An excerpt.

When I wrote about public spaces for City Journal 24 years ago, I called them “both the glory and shame of New York.” The glory because of “the liveliness,” then and now, “of our sidewalks and plazas”; and the shame because those spaces had become places of danger, filled with thieves’ markets, menacing madmen, and mounds of garbage—a key reason that, in 1991, pessimism about the city had been rising for six years, and half of all New Yorkers wanted to leave. In the later years of Ed Koch’s mayoralty and in the one-term tenure of David Dinkins, gunshots and the sound of whirring helicopters in search of the shooters were familiar. Abandoned cars, ripe for stripping, abounded, and the city was rife with the odor of urine and marijuana. Perhaps worst of all was the aggressive panhandling by not always homeless but usually mentally ill mendicants, who created an aura of menace.

But 20 years of mayoral leadership under Rudolph Giuliani and Michael Bloomberg brought a renewed energy and optimism to the city. The historic decline in crime began in the mid-1990s, when William J. Bratton, aided by George Kelling, cofounder of Broken Windows policing, first served as police commissioner under the newly elected Giuliani. After the proactive policing instituted by Giuliani and Bratton cleared the city’s public spaces, Giuliani’s successor, Bloomberg, aided by his police commissioner, Ray Kelly, expanded them, building the Hudson River Park, the High Line, and Brooklyn Bridge Park. Bloomberg also reinvigorated old spaces like Madison Square Park and Union Square. Over the past two decades, New York’s public spaces have reclaimed their former glory. Today’s residents, as well as tourists and business travelers, enjoy the city’s great advantage—the 24-hour pleasures of its public spaces—without worrying about safety. The pervasive sense of threat and the fear at the sound of trailing footsteps that once accompanied an evening stroll have largely receded into memory.

Success has bred its own problems, however. With the city’s rising population, subway crowding and car traffic are worse than ever. The sidewalks in Times Square overflow with tourists, who seem to find costumed characters like Elmo and Spiderman charming, even if some are unnerved by the topless women panhandlers known as the desnudas. New Yorkers are willing to overlook disturbances unimaginable in much of America. Earlier this year, my son Harry, a columnist for the Daily News, posted a picture of a packed outdoor café on Broadway and 21st Street. Yellow police tape extended from the edge of the café; directly around the corner from the diners stood a gaggle of cops. “Sunday brunchers, next to the murder scene,” he labeled the image.

But New Yorkers’ tolerance for the intrusion of unpleasant realities into everyday life only goes so far: some old concerns are starting to return. Though Gotham has seen record job growth in 2014 and 2015 and the city is approaching an unprecedented 4.2 million people employed, New Yorkers seem to fear that the city is going in the wrong direction. Asked if the quality of life has gotten better or worse in recent years, 53 percent say worse and only 14 percent say better. Several factors play into these perceptions, such as an increase in public smoking of pot and screaming tabloid headlines. New Yorkers sense something changing, and not for the better.

Much of this new unease seems to involve the rise in homelessness and increasing displays of disorder that take many new Gothamites by surprise while giving long-timers a chill of recognition. The city’s recorded homeless population grew by 10 percent in 2014. Sixty percent of New Yorkers told Quinnipiac in October 2015 that they see more homeless people “on the streets, in parks and on the subway” now than they did a few years ago. Just 11 percent say that they see fewer. Yet for almost two years, Mayor Bill de Blasio denied that increase, pointing to a once-a-year street census that took place during an exceptionally cold snap, when fewer homeless would be outside.

In a May 2015 interview with Rolling Stone, de Blasio, his approval numbers dropping, came off as a mayor in denial. “A lot of people outside New York City understand what happened in the first year of my New York City mayoralty better than people” within Gotham, he said. That analysis didn’t go over well, so de Blasio, backtracking, took to blaming the press and pollsters for his lagging support among New Yorkers. “I don’t say, ‘Oh, why doesn’t the public see through it?’ ” he told the Daily News in September. “I’m actually sympathetic—that if you hear the same [anti–de Blasio] message over and over again, it affects your judgment.”

De Blasio has tried to deflect criticism of his homeless policy by noting that the city produced 3,000 units of “affordable”—i.e., subsidized—housing last year, more than was brought on line from 2007 to 2013 under Bloomberg. He has promised many more units over the next 15 years. But these steps have done little to curb anxieties about homelessness.

De Blasio’s promises of gentler policing compound these worries. Overall, crime in the city continues to be contained, for which the mayor and his extraordinary police commissioner, William Bratton, back for his second tour of duty, deserve credit. But at the same time, de Blasio talks about a more discretionary treatment of transient people, an approach that, in practice, often puts police at a disadvantage in restoring order. The mentally ill homeless, in America’s only big city with a constitutional right to shelter, often don’t want help. If police need to wait for them to break the law to take action, they won’t get many of them off the streets.