By the logic of geopolitics, the United States and Iran ought to be cooperating to contain and weaken the Islamic State (IS). Both countries have declared that the group is a very serious threat to their own security and to the security of the entire Middle East. Indeed, it has become evident to all - besides those who are determined for their own reasons not to see it - that the army intent on setting up an Islamic caliphate has the potential to dissolve the basic international order that has...
