For sheer escalatory potential, look no further than the speed at which the six-day-old war in Iran has drawn in countries across the Middle East, causing the biggest energy shock since Russia’s full-scale invasion of Ukraine in 2022. While the long-term consequences of military action by the United States and Israel against Iran are unpredictable, worst-case scenarios for the global economy and markets have begun to unfold. Although the least important thing about any war is how it affects...