As ISIS has stormed down the Euphrates and taken towns, cities, and refineries, many have come to perceive the group as near-omnipotent. ISIS almost certainly believes that its military fortune is the result of divine providence. Nevertheless, just as occupations are complicated, managing limited military resources is also far from simple. The more territory ISIS controls, the harder the territory will be to hold (especially if it faces insurrections). From maps of territory presently under ISIS control, it’s clear that the group has vulnerable supply lines. Most estimates are that ISIS has under 10,000 combat troops, and dominating vast areas of both Syria and Iraq is a major task. And that’s just today. As Iraqi military pressure grows alongside new American support, ISIS will be forced to make hard choices about what to retain and what to surrender. The abovementioned factors surrounding ISIS ideology and governance will further complicate its ability to navigate this process. Even then, wherever ISIS tries to hold territory, it will be forced to adopt more-formal command structures and a more overt defensive military posture. Such adaptions will render the group vulnerable to U.S. intelligence monitoring and targeting.