NEW YORK ¨C The U.S.-Israeli-Iran war may be remembered for many things, not least the closure of the Strait of Hormuz, the reshaping of Middle Eastern geopolitics and the damage done to the global economy. But another consequence is less obvious: The largest oil-supply disruption in modern history has accelerated the arrival of peak oil demand.

Four months ago, the effective closure of the Strait of Hormuz triggered a global energy crisis. Oil prices surged, trade flows were disrupted, governments scrambled to shield consumers from rising costs and businesses were forced to adjust to an increasingly uncertain energy landscape. But amid the disruption, another trend emerged as countries began adapting to life with less oil. What began as a supply shock increasingly became a demand story, forcing the energy sector to reconsider one of its most important assumptions: the continued growth of global oil demand.

Before the war, the International Energy Agency projected that oil demand would ¡°rise by 2.5 million barrels per day from 2024 to 2030, reaching a plateau around 105.5 mb/d by the end of the decade.¡± The debate was not whether demand would continue growing, but how quickly growth would slow.

Now, the IEA forecasts that global oil demand in 2026 will be approximately 1.3 million barrels per day lower than expected before the war. Some of that decline reflects weaker economic conditions and higher prices, but the remainder reflects adaptation. Faced with constrained supplies and unprecedented uncertainty surrounding the world¡¯s most important energy chokepoint, governments and industries have accelerated their efforts to reduce oil dependence.

Markets have responded accordingly. Oil prices rise on renewed attacks and fall on reports of diplomatic progress. West Texas Intermediate crude ended the first week of June above $90 per barrel and Brent crude closed near $93. While prices have retreated from the highs reached earlier in the conflict, they remain roughly 30% above pre-war levels.

True, in the face of the largest supply disruption in modern energy history, the market response feels surprisingly restrained. But this relative calm masks a more troubling reality: Global inventories have been drawn down at a record pace, leaving considerably less cushion should the disruption persist. Before the conflict, roughly 125 to 140 vessels moved through the Strait of Hormuz daily. The waterway was viewed as vulnerable but dependable, with any prolonged disruption considered unlikely.

The past three months have demonstrated that the strait need not be formally closed to be functionally constrained. Reduced tanker traffic, maritime threats, mine deployments, insurance withdrawals, military operations and persistent uncertainty have disrupted trade flows and forced governments and companies to rethink long-standing assumptions about energy security. Even if a ceasefire is reached, traffic resumes and mines are...