Flowers for the victims at the scene of a stabbing on London Bridge, in which two people were killed, November 30, 2019Simon Dawson / Reuters

LONDON—In the past two weeks, the British Isles witnessed two important developments in the annals of jihadist deradicalization. The first, here in London, was a spectacular failure to deradicalize: Usman Khan, 28, feigned remorse for his participation in a 2012 terror plot and was let out of prison early. He was attending a conference on prisoner rehabilitation when he ducked into a lavatory, taped knives to his hands, and emerged to murder two conference attendees before being shot dead on London Bridge. The second development, in Dublin, was a test of willingness to bring another radical back into our midst. Ireland brought home Lisa Marie Smith, a 37-year-old mother and former member of the Irish military who traveled to Syria to live under the Islamic State, and charged her with membership in a terror group. Many in Ireland opposed the government’s decision to bring this accused terrorist home, rather than abandoning her to the miserable fate she chose for herself when she traveled to Syria five years ago.

There is something strange about the concept of deradicalization. The term implies a symmetrical relationship with radicalization, as if authorities could just reverse the transformation. But in practice the two processes are different, because deradicalization happens against the subject’s will in many cases, at the insistence of the government, and radicalization is organic and voluntary. Deradicalization therefore has a bit of a Clockwork Orange feel to it, even though no program that I am aware of uses techniques as coercive as the ones in Anthony Burgess’s novel or Stanley Kubrick’s film. Nor are real-life deradicalization programs as successful as those fictional techniques. (Would we even want them to be? Terrorism is scary, but a successful government mind-control program would be frightening in a different way.)

I have followed Smith for some time. She radicalized herself by studying the work of John Georgelas, the American jihadist and writer for Dabiq, the ISIS magazine. In 2014 she joined his family in Turkey and followed them into Syria. She lived with Georgelas’s household in the Islamic State’s de facto capital of Raqqah. For years her Facebook account functioned as a rebroadcasting service for Georgelas’s writing. (She posted her own work too—much less sophisticated, such as a July 2015 reminder that the Antichrist was on his way.) According to reports, she married a prominent British jihadist, Sajid Aslam, who is now dead. In interviews, most notably with the Irish journalist Norma Costello, she has repeated a familiar, self-exculpatory line: that ISIS went astray due to the corrupting influences of insufficiently pious members, not because of any inherent flaw in its millenarian, genocidal project.

In Ireland, unlike in the United States, mere membership in a terror group is a crime. I think Smith will have difficulty convincing anyone that she went to the land of the world’s most infamous terror group, while parroting its propaganda, without joining it. She might claim that she did nothing for the group—she did not provide “material support”—but the evidence I’ve seen makes her look like a witting member, and some have claimed that she taught children how to fire guns. ISIS children did not shoot recreationally; a few of the worst videos produced by the group showed elementary-school kids killing bound prisoners by shooting them in the head.

The Khan murders in London will revive fears that ISIS returnees are unrepentant, and that society should accept them back, if at all, with suspicion. Those fears are well founded. But Ireland’s return of Smith (and her daughter, born in Syria and an Irish citizen) was morally and strategically wise, and I hope the handling of her case becomes a sane template for managing returnees.

Of paramount concern, morally, are the returning children. Smith’s lawyer noted the perils that Smith has already faced, walking “through bombs, poverty, and cesspit camps, and desert, to come to her country of origin.” He meant, I think, to stress that Smith has already suffered for her choices. But a rational person would also observe that she chose this life not only for herself but for her daughter as well. The state routinely removes children from parents far less negligent than members of millenarian death cults. Smith should lose custody of her daughter until she has proved, against evidence, that she is not a homicidal maniac or supportive of people who are.

But how can she prove such a thing to a skeptical public? Khan successfully hoodwinked dozens of acquaintances, over the course of years. I sympathize with Simon Cottee’s scorn for liberal optimists (among them the Labour leader, Jeremy Corbyn) who thought Khan deserved another chance at freedom, merely eight years after aspiring to mass murder. That scorn is not for the belief in the possibility of redemption, but for the belief that society can correctly identify redemption when it happens. The soul can change. We’re just bad at making it change, and at figuring out whether the change is sincere. One of the few deradicalization treatments that seems to work reliably is the passage of time. Although some may still support violent groups, real violence tends to be a phenomenon of the young, just as it tends to be a male phenomenon. That is how A Clockwork Orange’s ultraviolent protagonist, Alex, was cured: by growing up.

If Smith is found guilty, she and others who have joined terror groups should be made to feel their youth drain away over the course of long custodial sentences. And while I would welcome their repentance, I would be reluctant to tell them what repentance looks like, so they can bark for me like trained poodles while secretly remaining jackals at heart.

I would hope that they would propose their own form of contrition. If you realized you had nearly killed your own child, and had supported the murder, rape, and enslavement of others, how would you make amends? I like to think I would prostrate myself in person before all those whom I had wronged, directly or indirectly, and beg them to name the price of their forgiveness. This task might take the rest of my life. When the last of them helped me to my feet and pronounced my debt repaid, I might begin to feel cured.

That virtually no one who supported ISIS has undertaken atonement along these lines suggests to me that the process of repentance remains incomplete, and that time in prison is still the only remedy we can confidently apply.

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