I first saw a “thin blue line” flag in person in 2016 or 2017, on a drive through rural Virginia. It was flying outside someone’s home.

Since then, though, I keep seeing it—we all keep seeing it—in places where it really shouldn’t be.

It’s very popular with law enforcement, and with people who claim to support law enforcement. But it worries me. Its design, and the way it’s being instrumentalized, point toward one of the darker, more divisive paths that the United States might follow from here, if we don’t change course.

The flag’s origins are noble: a symbol to pay tribute to police personnel who died in the line of duty. But imagery gets perverted quickly, especially in this very online era.

Pepe the Frog was just a comic character. The Punisher was a Marvel antihero. Both of their creators have since voiced horror at what each has come to represent. The same is happening to this flag design, even as police associations and conservative politicians embrace it.

The problem isn’t whether it’s an emblem of white supremacy, although it sometimes gets used that way. It’s a more fundamental problem with the design. It evokes division, separateness, a country coming apart.

Take a close look:

First, the celebratory red, white, and blue are replaced by somber, forbidding black and white. That’s fitting if the goal is to commemorate fallen officers: it’s solemn and funereal. But it also gives the design a dark, menacing simplicity. The sort of thing set designers would use in a fantasy movie with fascist badguys, like The Last Jedi or V for Vendetta.

Second, though, and far more troubling, is that blue line. “The stars represent the citizenry who stand for justice and order,” reads a site tailored for police, the first Google result for “thin blue line flag.” “The darkness,” it continues, “represents chaos and anarchy.”

This is how many police see themselves, and where the phrase “thin blue line” comes from: a human barrier protecting “good” people from the others.

You can guess the danger, though, can’t you? Who gets to decide who the “good” citizens are? Who gets to be north of the flag’s blue line, with the orderly stars, and who is south of the line, to be kept out and pushed away? And in any case, why slash a dividing line across a flag, the ultimate symbol of national unity?

At the local level, line-drawing is bad policing. Police should be part of a community, and that community’s members—of all races and backgrounds—should feel comfortable working with their local police. A community is secure only when the line is very blurred.

At the national level, to draw a line separating people in a polarized country, between “us” and “them,” is toxic. Right now, “us and them” is the language of the day, voiced at every Trump rally and throughout social media. In unequal societies of Latin America where I’ve worked for years, you sometimes hear of “la gente de bien” and “los sectores populares.” Same thing: a line dividing us and them. It doesn’t work there, either.

Who is on the other side of that line? Because this flag started showing up as a retort to the first Black Lives Matter protests against police killings—during the Ferguson/Colin Kaepernick moment—Black Americans can be excused for thinking that it is they who are the undesirables on the other side of that line. The flag’s appearance at white supremacist gatherings reinforces that.

So can people with left-of-center political views, those who want to expand rights and rein in unbridled capitalism. Donald Trump and other extreme GOP candidates appropriated this image and indelibly associated it with their election campaigns. Those of all races, ethnicities, sexual preferences, and belief systems who don’t belong to what Trump supporters consider to be the “real” America are excused for thinking that they, too, are included among the undesirables south of that blue line.

We’re not going to make it if our society persists in drawing lines between us, glorifying them with flags, and guarding them with armed force. This is how you sleepwalk into an armed conflict.

Police have a very hard job, not least because we ask them to do too many things that they’re not trained or prepared to do. Some, like Capitol Policeman Brian Sicknick, pay the highest price. All Americans should want police to have a professional career path, a dignified income, the esteem of the population, and the accountability that makes that possible.

All Americans should feel pain when a law enforcement professional dies on the job. And it makes sense to have a flag to commemorate it.

But not this one. It’s time for a new design.