By Jay Ogilvy As the Islamic State digs in after its conquest of Ramadi , U.S. President Barack Obama has been candid about his lack of a strategy to deal with the group, in part because he is waiting for commitments from the Iraqi government, but in part because the Islamic State is poorly understood. We know it is "nimble," "aggressive" and "opportunistic." But there is much about it we don't know. If you Google "books on the Islamic State," you might be surprised at how many have jumped off the press in the past year, a phenomenon all the more remarkable given how little we actually know about the group. One book you will not see among your search results, since it does not have "Islamic State" in its title, is the recently published Warlords, Inc.