The shots were fired 3,000 miles away in Brooklyn, New York, but they were heard across the nation.

In a flash, the sense of personal insecurity that has come to invade urban America of late had a name and a face and a nightmare to associate with it.

In Los Angeles, Metro announced that it would be adding more police presence to the cars that have increasingly been providing beds for the homeless.

Getting on a subway today? Thinking twice about it? Looking around at your fellow travelers with new suspicion? Or just staying home and saying the heck with it?

Criminologists have long recognized that the fear of crime exacts a toll on society distinct from crime itself. Every time you don’t go somewhere because why take the risk of the bus or the train or walking or whatever, the fear of crime has exacted a cost. Not crime, fear.

What is worse, of course, is that fear of crime is a self-fulfilling prophecy. If fewer law-abiding people ride the subway or walk at night or shop in the evening or go to the park, then all of those places become more dangerous, not less.

In a sense, we are back in the 1980s and ’90s, back in the days when it came to be recognized that dealing with the “incivilities” — the quality-of-life crimes from vandalism to graffiti that make a neighborhood or a train car feel unsafe — by encouraging a visible police presence working with the community rather than riding around in cars and only coming when called (usually to completed crime scenes where response times matter not at all) cut both crime and the fear of crime.

In Los Angeles, one of the most progressive cities in America, it is a measure of the level of fear and frustration that in the mayoral race, Rick Caruso, the billionaire developer who was recently a Republican, has pulled even with Democrat Karen Bass after a wave of advertisements promising that “Caruso can clean up LA.”

He’s right. About cleaning it up. If you make it feel safe again, if you can cut the fear of crime, you’ll cut crime as well.

And, by the way, only if you cut crime can my liberal friends hope to pursue a progressive agenda on crime and punishment. In my painfully long experience with the politics of crime, I can assure you that the more frightened people are in general, the less interest they tend to have in treatment and rehabilitation.

The original broken windows philosophy, promoted by my friends James Q. Wilson, George Kelling and Mark Moore at Harvard University, was based on the recognition that a car could sit untouched for days, but once the windows were broken, it would be stripped within hours. The signs of lawlessness breed lawlessness both directly and indirectly.

The answer in the 1980s was focused in large part on community policing. Instead of measuring police effectiveness by how quickly a car arrived at a long-completed crime, new measures and new methods sought to build partnerships with the community that would support a more active and visible presence in enforcing community norms.

At the same time, most major police departments were under various court orders requiring them both to reform certain practices and to increase their minority recruiting.

The hope was that a more representative police force that reflected the community could fairly enforce community standards — deal with gangs and graffiti, incivility and gun violence — in a nonracist fashion.

It is, to say the least, an unfinished agenda. The stubborn correlation between race and crime breeds institutional racism within even more representative departments. It is a challenge no one wants to confront but one that will complicate any effort to take back the streets.

In New York, no one is better positioned to take on the challenge than new Mayor Eric Adams (when he recovers from COVID-19). In Los Angeles, it may be a billionaire developer who sweeps in a tide of conservative frustration.

Until they do, the fear of crime will continue to take a huge toll.

Susan Estrich is a best-selling author, the Robert Kingsley Professor of Law and Political Science at the USC Law Center and was campaign manager for 1988 Democratic presidential nominee Michael Dukakis. Click here to read previous columns. The opinions expressed are her own.