Global oil markets operate with a margin of production capacity that is not currently being used. This spare capacity — oil wells that are drilled and capable of producing but are held back to manage price levels within OPEC+ target ranges — is the primary buffer that the market can deploy in response to supply disruptions. The overwhelming majority of it sits in the Gulf. In the event of a Hormuz closure, that spare capacity would be simultaneously the most valuable resource in global energy markets and the one most completely inaccessible, because the wells that hold it are connected to export terminals that require the strait to reach their buyers.

Every serious analysis of Hormuz closure scenarios eventually arrives at the same question: how much oil can get out without using the strait? The answer, consistently, is not enough — and understanding why requires examining the bypass infrastructure that exists, the infrastructure that has been proposed, and the fundamental mismatch between pipeline capacity and the volumes the strait normally moves.

The numbers establish the problem. On a normal day, somewhere between 17 and 21 million barrels of crude oil and petroleum products transit Hormuz. The combined nameplate capacity of all existing bypass pipelines is a fraction of that figure, and nameplate capacity is not operational capacity. The infrastructure must be maintained, staffed, protected, and in some cases reversed from its normal flow direction before it becomes useful in a closure scenario. The gap between what the strait moves and what the alternatives can handle does not close quickly.

Before a single missile is fired, before a mine is laid, before a naval vessel changes course, the insurance market registers the threat. War risk premiums on tankers transiting the Persian Gulf are among the most sensitive geopolitical indicators available. They move faster than official statements, faster than military repositioning, and faster than most news coverage. The underwriters at Lloyd’s of London are not strategists, but their pricing reflects a continuous aggregation of threat intelligence that rivals most government assessments.