CSIS Says U.S. Needs At Least Three Years To Replenish Iran War Missile Stockpiles

A new analysis from the Center for Strategic and International Studies (CSIS) says the United States will need at least three years to replenish stockpiles of key advanced weapons systems depleted during the 39-day war with Iran, including Tomahawk Land Attack Missiles and interceptor missiles used by Patriot and THAAD air defense systems.

“The United States has enough munitions for any plausible scenario in the Iran war, but rebuilding its depleted inventories will “take years”, according to a new report by the Center for Strategic and International Studies (CSIS)”

Al Jazeera

The War Zone reported that CSIS estimated the U.S. had about 3,100 TLAMs before the Feb. 28 launch of Operation Epic Fury and that U.S. forces lobbed more than 1,000 TLAMs at Iran during the conflict.

Al Jazeera

The same CSIS analysis described a “window of vulnerability” for a potential Western Pacific conflict, even as it said the United States has enough munitions for any plausible scenario in the Iran war.

AP said the CSIS report warned that “the depleted inventories have created a window of vulnerability for a potential Western Pacific conflict,” and that the time needed to rebuild inventories “has thus become a major concern.”

The AP report said President Donald Trump and Defense Secretary Pete Hegseth have insisted the U.S. is capable of fighting any war and that Chief Pentagon spokesman Sean Parnell told reporters the military “has everything it needs to execute at the time and place of the President’s choosing.”

Virginia Burger, a senior defense policy analyst at the Project On Government Oversight watchdog group and a former Marine officer, pushed back by saying Pentagon officials “knew the reality of our military stockpiles” and that “if we go to this fight” they would be drawing down to a critical level.

AP News

In a separate account, the Washington Examiner quoted CSIS author Mark Cancian saying, “There aren’t many near-term actions that can be done to fix the problem in the near term, actions all take time.”

The CSIS analysis also tied the replenishment challenge to production timelines, warning that “It takes time to expand production capacity and to build these complex systems,” and that the window of vulnerability would last “for several years until inventories return to their previous levels.”

Multiple reports linked the replenishment gap to U.S. defense plans toward Taiwan, with the AP analysis warning that depleted inventories could limit American firepower in any future conflict with China.

The War Zone said U.S. military leaders have suggested the People’s Liberation Army (PLA) could feel confident in launching an invasion of Taiwan by 2027, while the CSIS report described the stockpiles—especially Standard Missile-3s (SM-3) and THAAD interceptors—being degraded by more than a year of combat in the Red Sea region with Iranian-backed Houthi rebels.

The CSIS analysis also emphasized that the United States must rebuild while fulfilling allied demand, and the Hill reported that Ukraine remains in need of Patriot missiles while the U.S. remains poised to support 17 other countries that use the interceptor.

The Hill further said the Trump administration’s $1.5 trillion FY 2027 defense budget reflects “magazine depth concerns,” while CSIS warned that “there will be a window of vulnerability for several years” before inventories return to prewar levels and then another several years before they reach war-planner desired levels.