US Rapidly Depletes THAAD Missile Interceptors During Israel-Iran Conflict, Raising Stockpile Concerns

During the 12-day conflict between Israel and Iran in June, US forces expended approximately 25% of their high-end Terminal High Altitude Area Defense (THAAD) missile interceptors, according to sources familiar with the operation. More than 100, and possibly up to 150, THAAD interceptors were launched to counter a barrage of Iranian ballistic missiles, a usage rate that far exceeds current production levels. The US operates seven THAAD systems and deployed two in Israel during the conflict.

The rapid drawdown of interceptors has highlighted a gap in the US missile defense network and raised concerns among former defense officials and experts about the ability to quickly replenish these costly assets. Last year, only 11 new THAAD interceptors were produced, with 12 more expected this fiscal year, according to Department of Defense budget estimates. The Pentagon declined to provide specific inventory numbers, citing operational security, but stated that the US military remains prepared to respond to any threat.

Despite the heavy use of THAAD and other missile defense systems, dozens of Iranian missiles struck Israeli targets, causing significant damage in cities such as Tel Aviv and resulting in at least 29 deaths. Israel's tax authority estimated the cost of the conflict at a minimum of $1.8 billion. Analysis by the Jewish Institute for National Security of America (JINSA) found that THAAD interceptors accounted for nearly half of all successful interceptions, suggesting that Israeli stockpiles of similar systems were insufficient.

Experts warn that at current production rates, it could take three to eight years to replenish depleted interceptor stockpiles. "It is important to recognize the level of commitment and the level of expenditure here in defense of Israel is significant," said a missile defense expert monitoring US expenditures. Mara Karlin, former US Assistant Secretary of Defense for Strategy, Plans, and Capabilities, noted, "Air defense is relevant in all of the major theaters right now. And there’s not enough systems. There’s not enough interceptors. There’s not enough production and there are not enough people working on it."

The Department of Defense's 2026 budget proposal includes funding increases for missile and munitions production, with plans to acquire 37 THAAD interceptors next year. However, defense officials and analysts emphasize that production must be ramped up further to address the shortfall, especially given concerns about readiness in other regions such as the Indo-Pacific.

A senior retired US army officer confirmed that around a quarter of the THAAD inventory was used in the conflict, and said efforts to increase production capacity are underway. Former officials also expressed concern about the impact of these expenditures on US deterrence capabilities, particularly in light of ongoing tensions with China and other global security challenges.