The escalating confrontation between the United States and Iran bears all the hallmarks of a familiar disaster. Iran does not need to defeat the United States militarily. A war in the Gulf would send energy prices soaring, disrupt global trade, and deepen economic stress across Europe at a moment of already fragile growth. Europe’s security interests are not identical to those of the United States. European governments should insist on diplomacy over coercion, de-escalation over spectacle, and collective restraint over unilateral action.