The United States has run down a substantial share of its most important precision weapons during seven weeks of combat operations against Iran, leaving the Pentagon exposed to what defence analysts describe as a short-term shortfall that could take years to repair.
According to a new assessment by the Center for Strategic and International Studies, whose figures align with classified Defense Department stockpile data seen by three people familiar with the internal numbers, the scale of the depletion is striking. Roughly half of the military’s inventory of THAAD missiles — designed to intercept incoming ballistic missiles — has been used. Almost 50 per cent of Patriot air defence interceptors have been fired. At least 45 per cent of Precision Strike Missiles have been expended.
Why replenishment will take years, not months
The central difficulty for the Pentagon lies not in placing new orders but in waiting for them to arrive. Although a series of production contracts signed earlier this year is expected to expand manufacturing capacity, CSIS analysts and officials familiar with the stockpile assessments say replacement deliveries for the most heavily used systems will take between three and five years to complete.
That lag reflects years of relatively modest procurement. The CSIS report notes that recent agreements with private manufacturers will eventually raise output, but near-term deliveries remain constrained because previous orders were small.
Mark Cancian, a retired US Marine Corps colonel and co-author of the CSIS analysis, put the strategic cost in blunt terms. “The high munitions expenditures have created a window of increased vulnerability in the western Pacific,” he told CNN. “It will take one to four years to replenish these inventories and several years after that to expand them to where they need to be.”
Several other systems have also been significantly drawn down. The US has used around 30 per cent of its Tomahawk cruise missile stockpile, more than 20 per cent of its long-range Joint Air-to-Surface Standoff Missiles, and approximately 20 per cent of its SM-3 and SM-6 inventories. Replacement timelines for those weapons stretch to four or five years.
What the figures mean for a potential clash with China
Analysts are careful to distinguish between the immediate and the longer-term picture. In the short term, the US retains sufficient stocks to continue operations against Iran if the fragile ceasefire collapses. The concern lies further afield: the CSIS analysis concludes that remaining inventories of the most critical munitions are no longer adequate to sustain a confrontation with a near-peer adversary such as China, and that years will pass before stockpiles return to pre-war levels.
Those warnings had been anticipated within the military. Joint Chiefs of Staff Chairman General Dan Caine and other senior commanders had cautioned President Donald Trump before the war that a prolonged campaign risked depleting stockpiles — particularly those also being drawn on to support Israel and Ukraine — according to earlier CNN reporting.
A political disconnect over the scale of depletion
The assessment cuts against the administration’s public messaging. Chief Pentagon spokesman Sean Parnell told CNN the military “has everything it needs to execute at the time and place of the President’s choosing”, adding that since Mr Trump took office the armed forces had conducted “multiple successful operations across combatant commands while ensuring the U.S. military possesses a deep arsenal of capabilities to protect our people and our interests”.
The president himself has maintained that the US is not short of weapons, even while asking Congress for additional munitions funding tied in part to the Iran campaign. “We’re asking for a lot of reasons, beyond even what we’re talking about in Iran,” Mr Trump said last month. “Munitions in particular, at the high end we have a lot, but we’re preserving it.” He described the extra spending as “a small price to pay to make sure that we stay tippy top”.
On Capitol Hill, Democrats have voiced mounting unease about the pace at which weapons are being consumed and the knock-on implications for US posture in the Middle East and beyond. Senator Mark Kelly, Democrat of Arizona, summed up the underlying challenge last month. “The Iranians do have the ability to make a lot of Shahed drones, ballistic missiles, medium range, short range and they’ve got a huge stockpile,” he said. “So at some point … this becomes a math problem and how can we resupply air defense munitions. Where are they going to come from?”
For the Pentagon, that question now defines the coming years: whether industrial output can be scaled quickly enough to close a gap that, by its own internal measurements, has opened wider than officials have publicly acknowledged.
