The browser or device you are using is out of date. It has known security flaws and a limited feature set. You will not see all the features of some websites. Please update your browser. A list of the most popular browsers can be found below.
The Islamic State in Iraq and the Levant may claim to fly the flag of Islam, but the heart of ISIL is corporate. With assets over $2 trillion and a steady income of billions of dollars each year, ISIL has funded a land grab the size of Belgium with a population equal to New York City’s.
And many of its rank and file are lured far more by a slice of ISIL's oil money than the death of infidels. Three of the group's former employees spoke to us on the condition of anonymity.
Every night, 22-year-old Sevda would take the same road to the Turkish town of Hacipasa, separated from Syria by a thin river. Hacipasa is best known as a home to smugglers. The town reeks of oil.
Sevda would smuggle the stuff across the river.
"It comes from Syria, they bring it across the river," she explained. "They take it to their village, store it in their homes. And we go to their houses and get it from them."
Turkish soldiers recently discovered how smugglers like Sevda did their work, moving the oil across the river in jerry cans and then transporting it in vans or in secret gas tanks inside buses.
"We would construct a gas tank and make it bigger so it could hold 35, 40, 45, 50 gallons," she said. "If there was no army, you could make good money."
Sevda said she earned $400 or $900 or even $1,300 for a ton of oil. If she lugged over 10 tons, she could make $10,000 a night.
"Depends on how good you are," she said.
Hacipasa isn't friendly to outsiders "unless you come to buy diesel," Sevda remarked. After we filmed the jerry cans, smugglers stopped our car. It was only after Sevda negotiated on our behalf that they let us go.
It isn't just goods like gas that have been crossing the border, but fighters too. They star in ISIL's unprecedented social media campaign: hundreds of propaganda videos, highly produced, many featuring photogenic protagonists. Foreign fighters proudly reject their citizenship for membership in ISIL. A few dozen are American. Salam is the man who helped persuade them to join.
"They will follow anything you tell them," he explained over half a pack of cigarettes, in a discreet hotel room near the border with Syria. "Their brains are washed. We talk to them about religion, paradise and virgins."
For a relatively large salary, the 27-year-old IT expert, along with three others, would spend their days online.
"Almost all of it was lies, exaggerations," he said. "For example, we claimed other groups raped women. That wasn't true."
He said they would change the accounts' passwords every 12 hours and handwrote all their contacts in case they got hacked. The foreign fighters who already joined ISIL would pass on their friends' contacts, he said.
"Media is the most important thing for ISIL to attract foreign fighters," Salam said, "and create popularity in Syria and Iraq."
ISIL's popularity spans generations. The group calls them cubs: hands not large enough to hold assault rifles and minds not old enough to resist propaganda. Omar saw those children up close. He worked for ISIL in Raqqa, ISIL's headquarters, selling the goods that ISIL stole.
"What they work on most is recruiting children," he said, over tea on the Bosporus in Istanbul. "When children are brainwashed at a young age, they become strong willed and believe they will find redemption when they are martyred."
In Raqqa, men pray in the street and women stay covered. Local commanders called emirs, or princes, keep the peace.
"At first they brought in a thug, an alcoholic, a criminal, and appointed him emir," Omar said. "Now they've pushed them out. In their place they have appointed educated people who can have a strong presence and lead people."
The group is organized like a spiderweb, with the self-described caliph Abu Bakr al-Baghdadi and his deputies at its center. Each group of emirs and fighters is isolated, with no direct communication with leadership.
"They received orders but their source isn't known," Omar said. "Even the emirs within ISIL wouldn't know the original source of the information."
It was a complex and effective structure. And ruthlessness was the connective tissue of it all.
"They value spilling blood," he said. "They have no mercy. Islam is merciful. But for them, people's lives are cheap."