The US military’s weapons stockpiles, including its inventory of crucial air defense missiles, remain severely depleted following a major flare up of the war with Iran in recent weeks, according to three sources familiar with recent Pentagon data and a new report by outside analysts.

A substantive settlement to end the conflict remains elusive, and the shortage of the missiles could impact the US’ ability to engage on other fronts.

In a Monday report, researchers from the Center for Strategic and International Studies think tank estimated that fewer than 827 Patriot interceptors remain in US stockpiles, and fewer than 278 THAAD ballistic missile interceptors are left. The three sources familiar with the matter, who requested anonymity to discuss the US stockpile, told CNN that the CSIS estimates were close to internal government figures.

The figures represent a significant depletion of the pre-war stockpile, which CSIS estimated numbered around 2,200 Patriots (of the platform’s two most-modernized variants) and 452 THAAD missiles. The systems are the US military’s primary means of taking down incoming enemy ballistic missiles, and each interceptor missile costs millions of dollars.

“Diminished stockpiles may force the United States and its coalition partners to take more risks with interceptions. There are no good alternatives to Patriot and THAAD for ballistic missile defense. Navy ships, with Standard Missiles that can intercept such threats, generally are too far away,” the authors of the CSIS report wrote.

President Donald Trump expressed his desire to replenish “the more sophisticated stuff” when asked about munitions stockpiles aboard Air Force One on Monday, but the president held that the inventories are “in very good shape.” And Gen. Dan Caine, the chairman of the Joint Chiefs of Staff, told senators last week that without the additional funding it’s asking for, the Pentagon will “not get the munitions” it needs.

CNN previously reported that Caine cited the dwindling munitions stockpile in a Friday meeting with Trump during which the commander-in-chief was weighing a major escalation in the war. Trump, whom Caine and others briefed on additional downsides to ramping up the conflict, announced a pause in strikes against Iran after the meeting. But that pause may have been short-lived. On Tuesday US and Saudi forces conducted joint strikes on Iranian proxies in Iraq, and after the US military announced it intercepted a “surprise attack” by Iran on US forces in the Middle East.

The report’s lead author, CSIS defense analyst and retired Marine Corps Col. Mark Cancian, told CNN earlier this month that continued fighting with Iran could deplete stockpiles so low that it could impact the US military’s ability to fight with China or even North Korea.

NBC News reported that US commanders, motivated by a desire not to waste their interceptor missiles, are opting not to shoot down Iranian projectiles that are on track to hit unpopulated areas of US bases in the region. The reported tactic signifies a change from prior air and missile defense practices in the region, where a US-manned Patriot detachment defended a mostly evacuated Al-Udeid Air Base, Qatar, against a wave of Iranian ballistic missiles in June 2025.

The Defense Department has accelerated its efforts to expand interceptor missile production in recent months, including two deals inked this week to boost Patriot and THAAD rocket motor manufacturing, but a spokesperson declined to answer questions about when the expansion will lead to results.

Analysts say it could take years to fully replenish the US stockpile of high-end munitions, like Patriot missiles, due to the lead time for producing those weapons.

Chief Pentagon spokesperson Sean Parnell, in a July 28 statement identical to two sent to CNN on the topic since April, said the 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. 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.”

Trump and Defense Secretary Pete Hegseth have largely blamed former President Joe Biden’s administration for the munitions shortages. But the issue has been exacerbated by the war with Iran, during which CSIS assesses the US military has fired more than 60% of its key Patriot and THAAD interceptors.

The pending request from the Pentagon for supplemental defense funding includes several provisions related to the stockpile. Hegseth argued to Senate appropriators in a hearing on the supplemental funding ask last week that the Biden administration “took munitions one-for-one and sent them to Ukraine and had tried to replace them with the same bureaucratic process that was too slow and didn’t replace them in real time.”

But lawmakers of both parties have argued that the shortfalls are bigger than any one administration and require bipartisan support to resolve.

“The shortfalls in munitions have been well known to this committee for some time,” said Republican Sen. Susan Collins of Maine in last Tuesday’s appropriations hearing. “While these munitions shortfalls have been years in the making, they are growing increasingly urgent.” (CNN)

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