Is the US magazine of air defence interceptors deep enough to sustain a long campaign against Iran?
An SM-3 Block 1B interceptor is launched from the USS Lake Erie. (Photo: US Navy)
The Pentagon spent a considerable number of THAAD and SM-3 rounds to defend against Iranian missiles in 2025 and has not fully replenished its reserves.
In recent announcements, US authorities, including President Donald Trump, have claimed that the Operation Epic Fury against Iran could last for weeks. As Tehran responds to the offensive with ballistic missiles and drones, questions have been raised about whether Washington has enough air defence interceptors to protect its bases and partners in the region.
The concern is based on the number of rounds the Pentagon spent in 2025, which are yet to be refilled. This is certainly the case with the country’s Terminal High Altitude Area Defence (THAAD) missiles.
Seth G Jones, president of the CSIS Defence and Security Department,
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