Although the IS adheres to strict rules, its strategy is pragmatic. In the Syrian town of Kobani, the jihadists fought to the last man, but elsewhere they often quickly withdraw. The bloodlust they often stage in front of cameras belies the cool cost-benefit calculations that make them so successful.
The commander of the Badr militia, Hadi al-Ameri, reported in late January, for example, that his men had recaptured the northeastern Iraqi province of Diyala from IS. But, unlike the battle for Tikrit, there had hardly been any fighting. A bookkeeper for the IS explained what happened: "Hadi al-Ameri paid several million dollars for the withdrawal from Diyala." Sunnis who had fled Diyala, he said, were made liable for the sum paid to the jihadists. "They had to pay roughly $30,000 (€27,500) per village if they wanted to return," says the bookkeeper.
IS would hardly have been able to hold Diyala -- a Sunni-Shiite province -- because it shares a border with Iran. So the jihadists preferred to
take the money and retreat. In the past, they've frequently withdrawn from areas for similarly pragmatic reasons, only to recapture them later on. Their current goal seems to be the consolidation of their territory, and this requires money and combatants, not unnecessary fighting
