The Center for Strategic and International Studies (CSIS) released a report on Monday estimating that the United States now has fewer than 827 Patriot interceptors and fewer than 278 THAAD interceptors remaining in its stockpiles after weeks of intensified conflict with Iran. Three sources familiar with Pentagon data confirmed to CNN that the CSIS figures closely match internal government numbers, raising concerns about America's ability to defend against future threats.
Stockpile Depletion Details
Before the war with Iran, the US military held approximately 2,200 Patriot missiles and 452 THAAD interceptors. According to the CSIS report, more than 60% of these critical air defense weapons have been expended during the conflict. The Patriot and THAAD systems are the primary tools used to shoot down incoming ballistic missiles, with each interceptor costing millions of dollars to produce.
CSIS defence analyst and retired Marine Corps Colonel Mark Cancian warned that continued fighting with Iran could reduce stockpiles to levels that affect Washington's capacity to respond to threats from China or North Korea. “Diminished stockpiles may force the United States and its coalition partners to take more risks with interceptions,” the CSIS authors wrote in the report. “There are no good alternatives to Patriot and THAAD for ballistic missile defense.”
Impact on Military Operations
NBC News reported that US commanders are now choosing not to intercept Iranian projectiles heading for unpopulated parts of American bases in the region, a shift from previous practice, in order to conserve remaining missiles. This conservation strategy underscores the severity of the depletion, as field commanders adapt to limited resources.
Senior US military and congressional figures have warned that the shortfalls could affect America's ability to fight on other fronts. The concern is particularly acute given ongoing tensions with China and North Korea, both of which possess significant ballistic missile capabilities.
Government Response
President Donald Trump, speaking aboard Air Force One on Monday, acknowledged the need to replenish “the more sophisticated stuff” but insisted that US inventories were “in very good shape.” General Dan Caine, chairman of the Joint Chiefs of Staff, told senators last week that without additional funding, the Pentagon will “not get the munitions” it needs.
Chief Pentagon spokesperson Sean Parnell said in a July 28 statement that the military “is the most powerful in the world and has everything it needs to execute at the time and place of the President's choosing.” However, Republican Senator Susan Collins of Maine pushed back at a Senate appropriations hearing last Tuesday, stating: “The shortfalls in munitions have been well known to this committee for some time. While these munitions shortfalls have been years in the making, they are growing increasingly urgent.”
Replenishment Efforts and Challenges
The Defence Department signed two deals this week to boost Patriot and THAAD rocket motor production, though a Pentagon spokesperson declined to say when those efforts would translate into a meaningful increase in stockpile levels. Analysts caution that fully replenishing high-end munitions could take years, given the complexity of production and supply chain constraints.
Trump and Defence Secretary Pete Hegseth have pointed to the Biden administration's decision to send munitions to Ukraine as a key cause of the current shortfall. The CSIS report did not address this specific claim but highlighted that the depletion poses a strategic risk for the US military.
