The Iran war is rewriting the textbook on how open economies respond to geopolitical energy shocks, with the Bank of England voting unanimously to hold rates at 3.75% on Thursday and demonstrating a real-time case study in the monetary policy response to externally driven supply-side inflation. The monetary policy committee’s navigation of the competing pressures — external inflation risk from rising energy prices and domestic weakness from a softening labour market — represents one of the most analytically complex policy challenges faced by a major central bank in recent years. Officials warned that the conflict could push UK inflation above 3% and require rate hikes.
The textbook challenge begins with the identification of the shock’s nature. The Iran war has generated a supply-side shock to energy markets, transmitted to the UK through higher oil and gas prices. This differs from the demand-side inflation that conventional monetary policy is best suited to addressing. The textbook response to a supply-side shock is more nuanced — some degree of monetary tightening may be needed to prevent second-round effects, but aggressive tightening risks unnecessary economic damage.
Governor Andrew Bailey’s communications on Thursday reflected this nuanced approach. He said the Bank would act if inflation became entrenched through second-round effects on wages and prices but was not prepared to respond aggressively to the first-round energy price impact alone. His conditional, evidence-based approach was consistent with the textbook recommendation for measured responses to supply shocks.
Financial markets applied a simpler version of the textbook. UK gilt yields rose, the FTSE 100 fell, and the pound strengthened against the dollar as traders priced in rate hikes consistent with a standard inflation-fighting response. The market’s application of a more conventional tightening framework illustrates the tension between textbook sophistication and market simplicity in the current environment.
For students of monetary economics, the Bank of England’s handling of the Iran war episode provides a rich and timely case study. The real-world application of theory about supply shocks, open economy transmission mechanisms, and the communication challenges of uncertain policy environments will generate analysis and debate for years. Whatever outcome emerges from the current episode, its contribution to the practical understanding of monetary policy in open economies will be substantial.