ISIS will inevitably launch terrorist attacks on the United States. At present, however, the group is more focused on capturing land, territory, and resources, and fulfilling its dream of re-establishing the Islamic caliphate. ISIS’ proximate enemy is therefore not the United States, but any individuals, groups or governments standing in its path to statehood. As shown by its limited actions in Iraq, the United States has chosen to contain rather than destroy ISIS, and the group can certainly live with this. Having watched core al Qaeda sink into near irrelevance, ISIS has learned that, without secure territory, recruits and resources, it cannot confront the West. Indeed, even such a confrontation is just a means to a much broader, more ambitious end of de facto statehood.

Given the group’s limited size and ideological eccentricity, ISIS’ state-building project has been a surprising success. However, being a state carries obligations and commitments that expose ISIS to failure. By declaring a caliphate, ISIS committed itself to preserving and expanding its borders and controlling populations, including would-be dissidents. By projecting an image of confidence, control and inevitable victory, ISIS continues to attract local and foreign recruits, while co-opting its opponents or intimidating them into submission. Interrupting and rolling back some of its dramatic battlefield successes would have an enormous psychological impact, heartening its opponents, shattering its image of invulnerability and encouraging popular uprisings against it – insurgencies against the jihadist insurgents-turned-governors.

As an aspiring government authority, ISIS is also committed to providing public and social services to the population, activities in which it is already deeply engaged. These many public goods include power and water services, law enforcement, health care, dispute resolution, employment, education and public outreach. These responsibilities cost money, which in ISIS’ case comes from extortion (or taxation, as it were), control of energy and water resources, and plunder.