I'm glad you picked up on the idea of containment. The issue here, in a very short space of time, is that the Arab Muslim world and the region where ISIL is, at the heart and the core of the Arab Muslim world, is in huge, immense historical turmoil. There are all sorts of cross-cutting cleavages and relationships. Sectarian inter-tribal warfare has exploded. States are decaying or have failed. We are witnessing that. If you look at it and at the failed states indexes, we can see that the top 20 failed states in the world are basically Muslim states in this region.
What does that mean? There is no centre there holding the states together, and anarchy has been let loose.
The ideology of ISIL, the political message of ISIL, is wrapped in religious colours or in religious language, and that's what the people in the west are having difficulty understanding. But any student of Islam and Islamic history and Islamic politics, as we are, can clearly see that the ISIL ideology takes them back to the Middle Ages and, even beyond, to the earlier period in which we talk about the Salaf, the ancestors of Islam, the first few generations of Islam. They are committed to taking the world back to those ideas. These ideas are not simply those of ISIL.