2a Enemy disinformation, as well as simple error, can also set us on the wrong track. The enemy acts not just on the battlefield but also through an ability to influence our understanding of the situation by means of denial and deception. In this and other ways complexity reinforces uncertainty.1 The large number of actors involved in the Iranian situation would make it very difficult to discern clearly what is happening once the shooting starts, and the scene would remain very fluid as long as the fight persisted, and very likely for a good while afterward.2 As to the meaning of war, it may hardly seem worthwhile to probe something so self-evident, except that it is not self-evident anymore, if it ever was. A simple definition of war is the waging of armed conflict against an enemy, but this is too limited a concept in the 21st century. War in our time involves simultaneous conflict in the military, diplomatic, economic and social domains on four levels: political, strategic, operational and tactical.3 While a war with Iran might begin in the military domain, it would likely expand to others, and while it might begin at the operational or tactical level it would soon encompass strategic and political levels as well. How these twin expansions would take place has everything to do with context. All wars have one. Would a U.S.-Iran war break out during a protracted diplomatic process, or in the absence or abeyance of one? Would it happen during a period of increasing tension and military readiness, or out of the blue, after one party thinks that the dangers of war have subsided? Would the U.S. government assemble a broad “coalition of the willing’, just a few close allies-in-arms at the ready, or go it alone, even actively dissuading Israel from joining an attack? What would the domestic political situation be in the United States? Would there be an internal political consensus to act, or would there be an active, acrimonious debate? Would the American people be prepa