Pedestrians pass a political mural in Belfast, Northern Ireland.Toby Melville / Reuters

“We have to go, son.”

The young man trots down the stairs and climbs into a car. His mother drives in silence, tears gathering in her eyes. She stops near a parking lot. “I love you,” she says.

He doesn’t respond. He pushes the car door open and walks into the lot, behind some low-slung buildings. His breath grows rapid, ragged, anxious. Men in balaclavas approach.

Within seconds it’s over. A pop, a scream. “Again!” Another pop, another scream. He’s weeping on the asphalt; there are bullets in his legs.

His story is fictional—he’s an anonymous character in a shockingly violent public-service ad—but it’s representative of an old trend that is newly virulent in Northern Ireland. Two decades after the Good Friday Agreement formally ended the long-standing sectarian conflict between Catholics and Protestants there, and seemed to offer a template for ending civil conflicts around the world, a different kind of violence persists in working-class communities.

And the police have warned it is not going away.

“We call them ‘paramilitaries,’ but in bygone days a lot of them would’ve been called terrorists,” Anthony Harbinson, the Northern Ireland Department of Justice’s director of safer communities, told me.

The attackers are essentially gang members enforcing their own version of justice in communities where law enforcement is either unwelcome or fears to intervene. Sometimes they claim to be policing “anti-social behavior” such as drug dealing, but Harbinson says the perpetrators are often dealing drugs or participating in other criminal enterprises themselves and trying to protect their turf.

Unlike the violence that defined the Troubles, when members of different religious communities attacked each other in a struggle over British control of Northern Ireland, in these cases the assailants target their own.

“It’s not sectarian at all. What this is, is Catholic on Catholic, Protestant on Protestant,” Harbinson said. “It’s about control within their own communities.”

Northern Ireland’s struggle with paramilitaries illustrates just how complicated it is to end a war, even in the event of a successful peace deal. For many conflicts around the world, the Good Friday Agreement represents the best-case scenario of power-sharing and disarmament. But Northern Ireland’s continuing violence also shows how the societal distortions and the trauma of a long-ended conflict can continue to tear at communities, leaving them in a condition that’s not technically war but is far short of real peace.

The attacks take the form of shootings in the ankles, elbows, or knees (“sometimes all six,” Harbinson says), or beatings with hammers or clubs. The objective is not generally to kill, though some result in fatalities. Frequently, the victims know their attackers personally, since they all hail from the same close-knit communities. And often, as the new PSA depicts, the victims themselves show up, or their parents take them, to an appointment to be beaten or shot—they fear worse if they don’t.

Northern Ireland police say so-called punishment attacks like this are markedly higher than five years ago. But the origins lie in the deeper dynamics of the conflict, which didn’t so much end as shift into another domain.

The violence of the Troubles took some 3,600 lives over a 30-year period. When the Good Friday Agreement laid out provisions for a unity government and the disarmament of paramilitaries in 1998, sectarian violence across the country swiftly plummeted. Even then, though, there was evidence of a key problem left unsolved.

“It is a funny sort of peace in which people are regularly maimed and driven from their homes by paramilitary thugs,” wrote The Economist in 1999, a year after the agreement was signed. The punishment attacks weren’t mentioned in the accords; they weren’t, after all, the kind of Catholic-on-Protestant violence that the peace deal was meant to stop.

But the phenomenon had developed alongside the Troubles, for different reasons in different communities, explains Rachel Monaghan, a senior lecturer in criminology at the University of Ulster who has researched intra-communal violence in Northern Ireland. In the case of Catholic republican communities, who sought independence from British control, paramilitaries formed in opposition to—or defense from—the police. In Protestant loyalist areas, they formed as a kind of auxiliary to the authorities.

The phenomenon outlasted the Troubles. This year, one researcher on the Northern Ireland Policing Board tallied a toll of 158 deaths in “security-related” incidents in the 20 years since the Good Friday Agreement, most of them due to this kind of paramilitary activity. It was a total nowhere near the worst levels of the civil war, but one the researcher, Paul Nolan, told the BBC he found shocking.

“The violence has been turned inwards,” he told the broadcaster.

Those figures may even understate the prevalence of paramilitary activity, because many punishment attacks take the form of beatings or nonfatal shootings designed to intimidate rather than kill. At the post–Good Friday Agreement peak of such activity in 2001, the police counted 323 casualties tied to paramilitary activity, though given the distrust of police in many affected communities, this may be also be too low a number.

More recent statistics put the count near 90 annually for the past two years, compared with a post–Good Friday Agreement low of near 50 a decade ago. But the absence of other types of political violence renders these numbers especially stark, Monaghan said.

It persists even though communities can typically identify the assailants. Brenna Powell, a lecturer at Stanford Law School who has researched the Northern Ireland peace process, recalls meeting a teenaged boy who had been shot so many times with a nail gun that his hands were mangled. Every time he got attacked, Powell said, he knew exactly who was carrying it out. But the beatings didn’t stop, because he had nowhere else to go.

Powell cited high rates of suicide and drug abuse associated with the trauma of the conflict. “Does this kind of violence disappear in the absence of progress on all those other fronts? I don’t think so.”

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