The US military has significantly depleted its stockpiles of key missile interceptors, particularly THAAD and Patriot systems, due to their extensive use in the ongoing war with Iran. According to sources familiar with inventory reports and analyses from the Center for Strategic and International Studies (CSIS), the US has used nearly 80% of its THAAD missile inventory compared to pre-war numbers, and approximately half of its Patriot interceptors. Before the Iran war, CSIS estimated the US had around 452 THAAD missiles and 2,200 Patriot interceptors (of the two most-modernized variants).
Military commanders are warning that these munitions stockpiles are "dangerously low." This depletion raises substantial concerns about the American military's capacity to engage in a potential future conflict with major adversaries such as China, Russia, or North Korea. Experts, including retired Marine Corps Col. Mark Cancian, who authored a CSIS report, suggest that these shortages likely influenced decisions to pause air campaigns and will be a crucial factor in future Pentagon planning and presidential decision-making regarding the conflict.
Replenishing these depleted stockpiles will be a lengthy and expensive process. CSIS estimates that it could take at least three years, even with increased funding, to return supplies to pre-war levels. Specifically, replacing as many as 290 THAAD interceptors could take until the end of 2029, while replenishing over 1,000 Patriot interceptors is also a multi-year effort. Each interceptor missile costs millions of dollars, with some estimates placing the cost at around $4 million per missile, and production can take up to two years. The scarcity of these critical air defense systems leaves the US with few alternatives for ballistic missile defense.
