, the four-year-old civil war in Syria had forced more than 4 million people to flee their homes for neighboring countries. The impact of this outflow on Lebanon, Jordan, and Turkey-which has received the largest number of refugees at nearly 1.8 million 1 (UNHCR, 2015b)-has received significant press coverage. Discussion in the media of the crowded camp settings in particular-more than 200,000 are in Turkish camps and more than 100,000 are in Jordanian camps-as well as about clashes inside Lebanon between

Levant (ISIL), 1 propose a context in which ISIL should be judged (particularly ISIL's character and motivations, as well as key regional and global issues that frame the context), provide an initial framework for interpreting these insights, and outline a way ahead for developing and assessing courses of action and generating concrete options. This paper does not attempt to develop discrete courses of action or critique current ones; rather, it seeks to outline general principles that U.S. policymakers must consider when conceiving and weighing appropriate strategies to combat ISIL. Threats to U.S. Interests In the wake of the recent attacks in Brussels, Paris, and California, ISIL has demonstrated the will and capability to pose the threat of terror attack in the West, and it has shown an even greater threat to the Middle East, Africa, and South and Central Asia. What is not as clear is how threats to the countries and peoples of the Middle East affect U.S. core interests. These threats have longer-term manifestations, and nations in the region and close to it are, at least in the normal calculus of state power, far more capable than ISIL. Threats that remain at continental distances from the U.S. homeland for now but pose larger dangers than just terror attacks in the future are less certain and harder to determine. They are certainly possible, even if not currently manifest. Further, although military force could remove ISIL's control of territory, it could not eliminate the underlying ideology or support. Still, the question of why fighting ISIL is the business of the United States rather than that of Middle Eastern or European countries is a valid one. Defining the Context for Understanding ISIL Starting with ISIL itself and its so-called caliphate, we examine critical elements of the problem from the center and work outward to the global context.