Shelling in northern Syria as seen from the Hotel Istanbul, in Kilis, Turkey, in August, 2013. PHOTOGRAPH BY BEN TAUB

On a scorching afternoon in July, 2013, a taxi driver in southern Turkey pledged to take me from Gaziantep Airport to Kilis, near the Syrian border, for a curiously low fee. I had travelled this route twice before and was wary of favors, but a Syrian friend had vouched for this driver and arranged the pickup. So I followed him through the airport parking lot—past U.N. vehicles, a bus filled with arriving refugees, and bandaged fighters leaning on crutches—to his small yellow Opel, where it became clear why the price had been reduced: I was not the only passenger.

The man seated next to the driver had a long, dark beard, which brushed against his pristine white djellabah at the belly. He wore a traditional Muslim cap and clutched a leather purse in one hand and an iPhone in the other. I climbed in behind the driver and offered a quiet hello, but the passenger, who appeared to be in his thirties, did not glance back or return the greeting. For half an hour, the car hurtled south on the empty highway, past dilapidated homes and dusty, lifeless hills, and no one said a word. As we approached the outskirts of Kilis, I noticed that the passenger was reading an article from the Guardian on his iPhone_._ I leaned forward and asked where he was from. “London area,” he replied. He was “helping the brothers” in Syria as a field doctor in Azaz, a small town just across the border, which, at the time, harbored a fearsome ISIS presence. He asked where I would be staying, and I told him that I’d be in Kilis for the summer. Hearing this, the driver asked to confirm that my destination was the Hotel Istanbul, in the center of town. I wished he had not done so; after speaking to the passenger, I had resolved to disembark before reaching the address.

The Islamic State of Iraq and al-Sham was not yet a household name in the United States, but journalists and aid workers operating in the area feared the group more than any other and were leery of those associated with it. While encounters with other jihadi brigades were sometimes cordial, ISIS fighters were methodically transforming northern Syria into a black hole. Formerly known as the Islamic State of Iraq, the group announced its presence in Syria in April, 2013. By June it held at least eleven Western hostages, two of whom had been kidnapped out of a van I had once ridden in. That summer, ISIS terrorized Syrian villagers and murdered a child for blasphemy in front of his mother. Other rebel groups appeared reluctant or afraid to confront them. Taking on both ISIS and the Syrian government seemed an impossible task, rebels said as they stirred sugar cubes into tiny cups of tea at the Kilis cafés. Besides, ISIS occasionally helped break stalemates in battles against the regime.

The man in the front seat implored me to accompany him into Syria, promising I’d be in good hands. I declined, but asked for his name and phone number and proposed that we arrange a daytime interview in a public spot in Kilis. If he proved willing to meet on my terms, I wanted to understand what had drawn him to Syria. He deflected the invitation; it seemed our mistrust was mutual. He did, however, browse through his phone contacts and give me the number of his friend Malik, whom he said could be our intermediary. I asked again for his name. He replied inaudibly, so I repeated the question, and again, I didn’t quite catch it, but it sounded like “Afshar.” We had reached the bustling center of Kilis and pulled up in front of the Hotel Istanbul. I stepped into the hotel’s shadow. Afshar said goodbye, and the car continued down the border road.

The holy month of Ramadan was underway, so food and drink and sex and cigarettes could only be enjoyed after dark. Across the border, Ramadan meant an escalation in the intensity of battles, though fighters were tired, starved, and dehydrated under the blistering summer sun. On most days, the sounds of explosions in northern Syria would reverberate throughout Kilis’s dusty maze of streets. Rebels shared photographs of comrades’ corpses, claiming that they had reached paradise, and citing, as evidence, the smiles that had been pressed into their lifeless faces. They said the holy month was the best time to die as a martyr.

Back then, foreign jihadis streamed into Syria without discretion or consequence. They stretched off the twenty-hour journey from Istanbul at the bus stations in Kilis and Gaziantep. They logged their names in the guestbooks of border hotels, like the Paris Hotel, in Kilis, an apparent favorite among Chechen fighters, and the Hotel Istanbul, which was frequented by a peculiar mix of journalists, aid workers, war tourists, and jihadis. A growing number of hospitals and rehabilitation clinics hosted bedraggled foreign fighters, and sometimes jihadis crossed into Kilis just to take breaks from the war.

Roughly once a week, for the first three weeks, I called Malik and asked to speak with Afshar. He was never immediately available, but he always called me back a few minutes or a few hours later, sometimes from Malik’s number, sometimes from a blocked one. Our conversations were brief and predictable: I would invite him to break his Ramadan fast at a public restaurant in Kilis, and he would counter with the proposal of a home-cooked meal in Syria. I didn’t need to worry about transport, he said; he and his friends would pick me up in Kilis and drive me to their apartment. Finally, each of us would decline the other’s invitation and wish the other well, as if there were nothing strange about this ritual.

One night in late July, I was eating dinner with a Syrian activist, sitting on the floor of an industrial space he had rented to house his family, when the lights cut out. He and I stepped out into the street, a dusty block across from a park that had become an unofficial holding place for nearly three thousand refugees. From our vantage point, it appeared the entire town had lost power. All the nearby street lamps had been extinguished, along with the floodlights that usually illuminated the sand-colored minaret and dome of a nearby mosque. Mobile phones still worked, so the activist called a rebel contact on the other side of the border. The rebel claimed that a large supply of Ukrainian weapons was being driven from Turkey to Syria, to Ahrar al-Sham, an Islamist brigade with murky connections to Al Qaeda. The lights came back on roughly fifteen minutes later, and soon afterward I spotted a Syrian jet bombing very close to the border.

The Turkish government insists that such a transport was impossible—that it wasn’t supplying arms to rebel groups in Syria—but multiple reports indicate otherwise. In one case, trucks escorted by Turkey’s intelligence service were found to be transporting a thousand mortars and eighty thousand rounds of ammunition to the Syrian border, according to reports from the Turkish newspaper Cumhuriyet. The munitions bore Cyrillic markings and, according to a driver’s deposition, were picked up from a foreign airplane in Ankara. The government filed treason charges against the security forces who conducted the search, and President Recep Tayyip Erdoğan, who was then prime minister, said they had no right to stop trucks belonging to the intelligence service. A local governor, acting on Erdoğan’s orders, authorized the trucks to continue to the border. When Cumhuriyet published a (https://www.youtube.com/watch?t=104&v=8Gd515Gp7YQ%5D) taken during the search, a government prosecutor initiated a criminal investigation into the paper’s editor. Erdoğan personally accused him of “attempting to overthrow the government” of Turkey.