The U.S.-led operation to reclaim Mosul has created a religious rift within the Islamic State (also known as ISIS). Of course, the terrorist group has always had a complicated relationship with Islam—much of the Muslim world disavows the group. But now, faced with the pressures of impending defeat, some fighters have abandoned ISIS’ strictures, such as bans on alcohol and cigarettes, which has irked those who are more dogmatic about the enforcement of sharia law. This has created a deep split over the group’s doctrine. 

The ISIS members most affected by the impending collapse of Mosul are foreign fighters. As their forces crumble, they have few options. Unlike local members, they cannot remain in Iraq because they stand out among locals and do not speak the language. For the same reason, it is difficult for them to blend in with refugees. They understand that they will most likely die, and soon. As a result, some foreign fighters have responded to this grim reality with a renewed religious fervor, as they believe doing so will allow them to die a shaheed, or one who has died fulfilling a religious commandment. A popular theological book among the Russian-speaking ISIS community, for example, is the Book of Jihad, which teaches, “If you will be killed in jihad, all your sins will be forgiven.”

But their religious turn has put them at odds with other members who are drinking and smoking to relieve the pressures of war. According to civilians we spoke to in Mosul, some fighters are now openly smoking on the streets of the self-proclaimed caliphate (although it is still strictly forbidden for civilians). Iraqi military forces told us that they have noticed an increasing prevalence of empty whiskey and beer bottles on captured ISIS bases. And neither is ISIS settling for cheap, local varieties. At one abandoned ISIS safe house in Mosul, the forces found White Horse whiskey, a Scottish brand that costs around $44 a bottle in Iraq. Civilians in Mosul also told us that they had begun to notice ISIS fighters drunk on the streets, especially close to the frontline and in areas where Russian and Central Asian ISIS militants are based. Some civilians from Zahure, a recently liberated neighborhood in Mosul, also reported seeing intoxicated fighters the night before an operation.

Those among ISIS’ top command appear to be willfully ignoring such transgressions. In fact, ISIS emirs not only have turned a blind eye to the smoking and drinking but have actively participated in alcohol and cigarette smuggling, a highly lucrative business. According to an Iraqi officer in the Hash al-Ashayari, a tribal mobilization force, he had caught smugglers in December 2016 attempting to sell cigarettes for 6,500 dinars ($5.50) a pack inside ISIS-controlled territories, an enormous markup from the standard price of 2,000 dinars ($1.70). The smugglers told him that ISIS emirs were taking healthy cuts from those sales.

Fighters who were attracted to ISIS because of the group’s ideology, however, are appalled by such nonchalance. But when they object, they have been treated as traitors.

Mohamed was one such fighter. (His name has been changed to protect his identity.) He is from Central Asia and joined ISIS in 2013 to fight President Bashar al-Assad’s regime in Syria. He said he had been deeply moved by the videos of civilians dying in Syria. But since joining, he has become extremely disillusioned by ISIS’ apparent hypocrisy and he fled the group about a year ago.

Although Mohamed was only nominally religious when he first joined ISIS, after watching his friends perish on the battlefield, he grew fearful of dying as an untrue Muslim and began studying the Koran in earnest. “The more I was reading about Islam, the more I realized how ISIS was not Islamic,” he said. He pointed out that the increasing bureaucracy within ISIS seemed non-Islamic to him and the sharia court was not actually implementing sharia, as its decision-making had been corrupted by nepotism and bribery. “There were cigarettes being sold everywhere,” Mohamed told us. “What kind of a strange caliphate was that?”

In reaction, Mohamed, together with a friend, an Egyptian fighter, organized a small group of eight soldiers to teach other ISIS members about Islam. “We were telling others, do not listen to Abu Bakr or anyone else, only read the Koran and Sunna,” Mohamed explained. “You can find all answers there.”

But such thinking was not looked upon favorably by the increasingly paranoid ISIS leadership, and before long, he and his friends were being monitored. “They had black cars, and their agents were wearing masks,” Mohamed said of the ISIS members who serve as the group’s internal security and who began to follow them. He noticed that ISIS members who had also questioned the group’s doctrine had disappeared.

Although most of these ISIS members were imprisoned, Mohamed told us, members of the local internal security service, which is tasked with rooting out dissenters, claimed that these members had been invited to visit the self-proclaimed caliph, Abu Bakr al-Baghdadi, supposedly to talk about Islam. Some fighters believed it, Mohamed told us. But in reality, those arrested were deemed kafirs, or nonbelievers. Instead of being held in a regular prison and appearing in front of a sharia court, said Mohamed, they were shipped directly to internal security prisons, which are usually reserved for death row inmates such as spies. Clearly, ISIS saw them as serious threats.

When Mohamed noticed that his Egyptian friend had disappeared, he believed he would be next and fled the next day. He managed to escape and is now hiding in Ukraine. He regrets having joined ISIS and wishes he had never left his native country in Central Asia. “I should have stayed, studied true Islam, and taught it to people,” he said. 

As with any internal disagreement within ISIS, the religious disputes are destroying group cohesion. But ISIS views those toting true Islam as capable not only of sabotaging the group from the inside but also of acting as a powerful deterrent to potential recruits. And without being able to tote its so-called Islamic credentials, the Islamic State will be seen as nothing but a state—and an abusive, corrupt one at that.

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