The Bill

The United States has burned through nearly half of its most critical missiles in seven weeks of war against Iran. That is the finding of a Center for Strategic and International Studies report published on Tuesday, and internal Pentagon figures are consistent with the analysis. Forty-five per cent of Precision Strike Missiles. Over half the THAAD interceptors. Close to 50% of Patriot air defence missiles. More than 30% of Tomahawks. Over 20% of JASSMs. Similar figures for SM-3 and SM-6 interceptors.

The report's conclusion has two parts, and the second is the one that matters. First: the United States has enough missiles to keep fighting Iran under any plausible scenario, even if the ceasefire collapses. Second: what remains in the stockpiles is no longer sufficient to confront a peer competitor, particularly China. Mark Cancian, a retired Marine Corps colonel and co-author of the report, said the expenditures have created "a window of increased vulnerability in the western Pacific."

How is the operation still sustainable if inventories are this low? Because missile consumption dropped sharply after the opening days of the war. For ground attacks, cheaper and more plentiful munitions largely replaced the long-range missiles. Iranian drone and missile attacks fell off steeply after the first week, cutting air defence expenditure. The intensity of the opening phase was exceptional. After that, the war became cheaper to run, but the damage to inventories was already done.

Rebuilding will take one to four years to return to pre-war levels. And several more years beyond that to reach where they need to be for a Pacific conflict, levels that were already considered insufficient before the war began. The administration has signed agreements with industry to quadruple production of "exquisite class" weaponry, but near-term deliveries are low because past orders were small. Even if Congress appropriates the requested FY 2027 funds, those missiles will take years to arrive.

Trump said at the start of the war that munitions stockpiles had "never been higher or better" and that the United States had a "virtually unlimited supply." Pentagon spokesman Sean Parnell insists the military "has everything it needs to execute at the time and place of the President's choosing". The CSIS maths says otherwise. There is an implicit bet in the decision to spend at this rate: that it is better to win the war you are fighting than to hold back for one that may never come. Reasonable enough, as long as you trust that China will not make a move while the Pacific is under-stocked.