We hear a lot about foreign fighters inspired by propaganda and willing to give up their homes to fight for the Islamic State. Less discussed are the Islamic State�s plans for the unwilling, captured in conquest. The Islamic State, also known as ISIS, would much prefer enthusiastic members to coerced subjects, but is it ever possible for the unwilling to become the willing? In an article for Studies in Conflict and Terrorism, I argue that it is. We have seen a movement generate religious extremism among captives, not that long ago. But this one wasn�t Islamist.

In the late 1980s, Joseph Kony turned a flagging Ugandan political rebellion into a charismatic millenarian insurgency. The Lord�s Resistance Army (LRA) was centered on the �holy spirits� possessing Kony. Blending Christianity with local Acholi cosmology, the LRA aimed to capture and rule Uganda according to the Ten Commandments. This was hard to reconcile with the LRA�s large-scale abductions and massacres perpetrated on Acholi civilians, whom they claimed to be fighting for.

This movement overwhelmingly relied on abduction to fill its ranks. Yet, paradoxically, a strikingly high proportion of LRA abductees felt belief in Kony�s powers, and even devotion to him. One study reports that 44 percent of former abductees expressed feeling loyalty to Kony for a time. Kony did this by creating a new religious universe, in which he would �purify� the Acholi of their sins and usher in a reborn moral order. His captives were forced to immerse themselves in this universe to survive.

Strange though the comparison may sound, ISIS has had to do the same thing. It has no major allies in the Muslim world; even jihadist scholars have condemned it. It has had to construct its own religious authority. Trying to understand ISIS purely as a product of Salafi ideology misses this point. Even the most literal schools of Islamic law have built up practices of authenticating textual evidence over centuries. ISIS shamelessly flouts these conventions when it tries to justify its atrocities with reference to religious texts, relying on hadith (recorded sayings of the prophet Muhammad) that Islamic scholars consider unreliable. If they are to get away with this heterodoxy, they must demonstrate another kind of authority, something more mystical.

Comparing the two groups, patterns emerged. Entering either group � via abduction in the LRA, or being conquered by ISIS � is a terrifying experience. In the LRA, beatings and forced marches to distant camps were often followed with an initiation by ordeal. In extreme cases, abductees were forced to kill friends or family. In Acholi cosmology, spirits of the murdered haunt their killer, bringing terrible misfortune. Yet in forcing abductees to kill, and then �purifying� them in an initiation rite, LRA commanders showed no such fear. They demonstrated that they have a more powerful spirit, Kony�s spirit, on their side.

ISIS�s displays of sectarian violence, are, likewise, partly for show. When it massacres Shias and Yazidis, it also signals to its Sunni captives that those who are �in� gain ISIS�s protection, while the consequences of being �out� are fatal. ISIS also shatters taboos to mimic divine association. When its members burned Jordanian pilot Muath al-Kasasbeh alive, they violated a belief that death by fire can be inflicted by Allah alone. The act was condemned by Islamic authorities around the world. Through this defiance, ISIS implied direct access to the divine, painting itself as the hand of God, above human authority.

Again in both groups, once �in,� captives must learn the rules that govern all aspects of life. Kony�s spirits issued rules against moving slowly, smoking, drinking, eating pork, harming bees, and many more offenses, including imposing periods of fasting. Stories of what happened to rule-breakers were rife. A former abductee said those who ate during a fast would inevitably be shot in the mouth, since the spirits would only protect those who obeyed.

In Raqqa under ISIS, the morality police, al-Hisba, patrol the streets in vehicles fitted with speakers, preaching behavioral regulations. Posters displaying rules are around the city. The horrific punishments for rule breaking, including� amputation, lashing, crucifixion, and beheading, are carried out in the main town square. While such punishments are meant to be subject to judicial process, what�s publicized are the gruesome punishments, not the legal safeguards.

But captives come to see these very tools of coercion as lifelines. Adhering to the rules gives them a way to mitigate fear amid violence, and assert control amid chaos. These rules are framed within narratives of the end of the world. Millenarian or apocalyptic narratives are about �purity.� If groups can convince their captives the world is ending, that urgency can frame �cleansing� violence as righteous.

Kony claimed he was sent to punish the Acholi for their sins. A former senior commander told me, � . . . he [Kony] said . . . if God has called you to bring judgment to anybody . . . you must kill them, but don�t torture them.� Death is sanitized, necessary rather than sadistic. Once the sinners were dead, a new moral age would arrive.

ISIS recounts apocalyptic myths of a final battle between the Muslims and the armies of Rome at Dabiq in Syria, after which the righteous will enter Paradise. A search for �signs� of the apocalypse is a favorite activity of ISIS�s Twitter users. But ISIS will not convince just by preaching apocalypse; it must stage apocalypse. This is the reason for its terrifying atrocities. If conditions didn�t feel apocalyptic, how would it be known these prophecies were coming true?

Both ISIS and the LRA offer their captives the chance to stay alive, and to triumph in the impending apocalypse, so long as they follow the rules. We don�t know if this strategy works for ISIS, but if it does, it must be recognized as a coping mechanism. As with the LRA, this forces difficult questions about captives� culpability in combat.

This comparison might help us avoid being blindsided by the �Islamic� in ISIS�s name and forgetting lessons we have already learned.