The U.S. may have burned through roughly half of its Patriot missile interceptors during the conflict with Iran, according to a new analysis, underscoring how even a campaign lasting just weeks can place heavy strain on key munitions stockpiles.
While the U.S. still has enough firepower to sustain operations in the current fight, analysts warn the greater risk lies in a future conflict against a peer adversary.
A report from the Center for Strategic and International Studies (CSIS) found that U.S. forces used large shares of several critical munitions during the 39-day air and missile campaign, including more than 850 Tomahawk cruise missiles and more than 1,000 Joint Air-to-Surface Standoff Missiles (JASSMs). Patriot interceptor use was estimated between roughly 1,060 and 1,430 missiles — more than half of the U.S. prewar inventory.
Exact U.S. munitions stockpiles are classified, and the figures in the report are estimates derived from Pentagon budget documents, historical procurement data and reported battlefield usage.
TRUMP RALLIES DEFENSE TITANS TO SURGE WEAPONS OUTPUT AS IRAN WAR RAGES
Even before the Iran war, U.S. stockpiles of key precision munitions were considered insufficient for a large-scale conflict with a peer adversary such as China. The latest drawdowns have made that gap more acute. A future war in the Western Pacific would likely require sustained use of the same high-end missiles now being depleted, particularly for long-range strike and missile defense against a sophisticated adversary.
Other high-end systems were also heavily drawn down.
The U.S. is estimated to have used between 190 and 290 Terminal High Altitude Area Defense interceptors, which cost about $15.5 million each, and between 130 and 250 SM-3 interceptors, among the most expensive in the arsenal at roughly $28.7 million apiece.
The Navy’s SM-6 missile, which costs about $5.3 million per unit, also saw significant use, with estimates ranging from 190 to 370 fired.
Long-range strike weapons used in the conflict carry similarly high price tags.
Tomahawk land attack missiles cost about $2.6 million each, while JASSMs are priced at roughly $2.6 million per missile. The Army’s newer precision strike missile (PrSM), costing around $1.6 million per unit, was also used in smaller numbers, with estimates ranging from 40 to 70 fired.
Pentagon chief spokesperson Sean Parnell denied reports of stockpile shortages.
“America’s 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,” he said in a statement.
“As Secretary Hegseth has highlighted numerous times, it took less than ten percent of American naval power to control the traffic going in and out of the Strait of Hormuz. Since President Trump took office, we have executed multiple successful operations across combatant commands while ensuring the U.S. military possesses a deep arsenal of capabilities to protect our people and our interests. Attempts to alarm Americans over the Department’s magazine depth are both ill-informed and dishonorable.”
A Navy official added to Fox News Digital: “The Navy is taking aggressive steps to increase our munitions stockpiles and strengthen the industrial base; as reflected in our FY27 budget request of $22.6 billion, which will fund over 4,600 all-up rounds.”
“We are significantly increasing production for our most critical systems, including the Standard Missile, Tomahawk, AMRAAM, and the PAC-3. To support this surge and provide a stable demand signal to our industry partners, we are continuing the multi-year procurements for LRASM and NSM, while initiating new multi-year contracts for the Tomahawk and Standard Missile. We are also working with the Department of War through the Munitions Acceleration Council (MAC), to synchronize efforts across the enterprise to break down barriers and speed up production.”
The Pentagon’s latest budget request underscores the urgency: The administration is seeking roughly $70 billion for munitions in fiscal year 2027 — a nearly threefold increase over current levels — as it moves to replenish stockpiles strained by recent conflicts, including Iran and Ukraine. The request includes sharp increases in purchases of key systems used in the war, including Tomahawk cruise missiles, Patriot and THAAD interceptors, and long-range strike weapons.
Iran maintains thousands of missiles and drones, according to Defense Intelligence Agency director Lt. Gen. James Adams.
“Despite significant degradation of Iranian military capabilities through coalition strikes in operation Epic Fury Tehran retains thousands of missiles and one-way attack UAV’s capable of threatening U.S. and partner forces throughout the region,” he told the House Armed Services Committee Wednesday.
IRAN’S REMAINING WEAPONS: HOW TEHRAN CAN STILL DISRUPT THE STRAIT OF HORMUZ
Despite the heavy expenditures, the U.S. retains enough munitions to sustain operations in the current conflict. The report notes that after heavy use of long-range missiles in the early phase of the campaign, U.S. forces shifted toward less expensive and more plentiful weapons, including Joint Direct Attack Munitions and other short-range systems.
The concern, analysts say, is what comes next.
Rebuilding those inventories will take years. According to the CSIS analysis, delivery timelines for many of these systems range from roughly three to more than five years, factoring in contracting delays, production lead times and manufacturing capacity limits.
That lag comes as global demand for the same systems continues to rise. Patriot interceptors, for example, are in high demand among U.S. allies, including Ukraine, which has relied heavily on them for air defense. Other partners in Europe and Asia are also seeking to expand their own stockpiles, creating competition for limited production capacity.
The Trump administration has pushed to rapidly expand production of key munitions, with defense contractors planning major increases in output. Lockheed Martin, for example, is aiming to boost Patriot interceptor production from roughly 600 per year to about 2,000 by the end of the decade, while also expanding THAAD interceptor capacity from under 100 annually to several hundred. RTX has said it will increase Tomahawk production to more than 1,000 missiles per year, a significant jump from recent levels.
But those increases will take time. In its latest budget request for fiscal year 2027, the Pentagon is calling for a surge in munitions procurement, yet analysts caution that even with additional funding and planned production gains, the defense industrial base cannot quickly replace weapons already expended.
Pentagon officials had already raised concerns about U.S. munitions stockpiles after years of military support for Ukraine. In 2025, the Pentagon paused shipments of some air defense missiles and other weapons to Kyiv following an internal review that found certain inventories had declined too far.
The strain is already affecting U.S. allies in Europe. U.S. officials have warned that some previously contracted weapons deliveries to European countries—including in the Baltic region—could be delayed as the Iran war draws down American stockpiles.
Leaders in Estonia and Lithuania said they had been informed that delivery timelines for U.S. military equipment were shifting, with some ammunition shipments “put on hold” as Washington works through supply constraints.
One European defense official told Fox News Digital that delays could have longer-term consequences, warning that allies may begin to “rethink” future purchases of U.S. weapons if delivery timelines become unreliable.
The production bottlenecks are not new. The U.S. has faced a backlog of more than $20 billion in approved weapons sales to Taiwan, with delivery timelines for some major systems slipping by years due in part to limited industrial capacity.
During the conflict, the Pentagon moved elements of its Terminal High Altitude Area Defense (THAAD) system from South Korea to the Middle East to bolster defenses against Iranian missile attacks, according to multiple reports. The redeployment highlights the tradeoffs facing U.S. planners as they shift limited high-end air defense assets between regions.
The result is a growing challenge for U.S. defense planners: sustaining current conflicts while preparing for a potentially larger war ahead.
Fox News has reached out to the Pentagon and relevant service branches for comment.