Iran War Has Led to U.S. Munitions Shortfalls, Pentagon Inspector General Confirms

By Angel No Lie | KPD Online | September 16, 2026

WASHINGTON — A new Pentagon inspector general report has confirmed that the U.S. military’s war with Iran has produced strategic shortages in some munitions inventories and exposed bottlenecks in the American defense-industrial base responsible for replacing them.

The findings were contained in the first Lead Inspector General report on Operation Epic Fury, the U.S. military’s designation for the conflict. The report was released September 14 and covers operations through June 30, 2026.

According to the report, the United States spent an estimated $33.4 billion on the operation between February 28 and June 30, including approximately $22.3 billion on munitions. The inspector general said that expenditure had resulted in strategic inventory shortfalls and revealed production bottlenecks affecting the ability to replenish weapons.

What the Pentagon watchdog found

The report identifies several areas where the defense-industrial base faces difficulty increasing production quickly.

Among the persistent constraints are:

• Solid rocket motor production
• Availability of high-grade explosives and propellants
• Recruitment of skilled manufacturing workers
• The time required to expand production capacity
• Procurement and production lead times for sophisticated weapons

The Pentagon is working to streamline procurement and production processes and to stockpile critical materials and components, according to the inspector general. However, the report cautions that expanding the industrial base requires significant lead time.

The findings do not mean that the U.S. military has run out of ammunition. Rather, they indicate that inventories of certain weapons have fallen below levels considered strategically desirable and that rebuilding them will take time.

Advanced missile inventories under pressure

The issue is particularly significant for expensive precision weapons and missile-defense interceptors.

The Congressional Budget Office, in a separate report released September 15, estimated that the United States had spent about $38 billion on the conflict through August 1. CBO estimated that replacing expended munitions would cost approximately $21.7 billion, including about $13.1 billion for interceptors and $7.3 billion for land-attack cruise missiles.

CBO also said the United States had used between one-half and two-thirds of its inventory of certain interceptors since June 2025, taking into account both the Iran conflict and other operations. It estimated that rebuilding those inventories could take at least five years.

The assessment is particularly relevant to systems such as Patriot and THAAD interceptors, which are designed to defend against ballistic and other missile threats, as well as long-range weapons including Tomahawk cruise missiles.

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War has also damaged U.S. military infrastructure

The inspector general’s report goes beyond weapons inventories.

Iranian attacks damaged or destroyed hundreds of buildings and other structures at U.S. military installations across the Middle East, according to the watchdog’s assessment. Facilities in Kuwait, Bahrain, Qatar, the United Arab Emirates, Saudi Arabia, Iraq, Oman and Jordan were among those affected.

The report also recorded damage to U.S. diplomatic facilities in Iraq, Kuwait, Saudi Arabia and the UAE, with reported damage of approximately $184 million.

Military equipment was also lost or damaged. The report documented damage involving aircraft including F-15E fighters, an F-35A, KC-135 refueling aircraft and helicopters, while up to 30 MQ-9 Reaper drones were reported destroyed or damaged.

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A broader cost is emerging

The munitions shortage is part of a wider financial and logistical burden.

The CBO’s September 15 assessment put the Defense Department’s cost of the conflict at approximately $38 billion through August 1. It said monthly costs could run between roughly $2 billion and $3 billion, depending on the intensity of combat.

CBO also noted that its estimate does not include every federal cost associated with the conflict and that the Defense Department did not provide requested information to the budget office, meaning the estimates carry uncertainty.

The report’s assessment of the munitions drawdown is therefore separate from the Pentagon inspector general’s June 30 accounting: the IG reported $33.4 billion in costs through June 30, while CBO subsequently estimated approximately $38 billion through August 1 using its own methodology.

Pentagon response and continuing debate

The findings have generated renewed debate over the condition of America’s weapons stockpiles.

President Donald Trump has publicly maintained that the United States has substantial weapons supplies and that production is being increased. Pentagon officials have also disputed descriptions suggesting that the U.S. military is unable to conduct required operations. Reuters reported that a Pentagon spokesperson said the military had what it needed to conduct strikes when directed.

The inspector general’s finding is more specific: certain inventories have experienced strategic shortfalls, while the defense industry faces constraints in replacing them.

Those positions are not necessarily mutually exclusive. A military can retain the ability to conduct current operations while simultaneously having inventories below desired levels or facing a lengthy process to restore them.

Why the findings matter

The reports raise questions about how quickly the United States can rebuild sophisticated weapons inventories after a high-intensity conflict.

The issue is particularly important because many advanced weapons cannot simply be replaced by increasing orders overnight. Production depends on specialized factories, components, explosives, propulsion systems, skilled labor and lengthy manufacturing and testing processes.

CBO’s assessment indicates that the consequences could extend beyond the Iran conflict, because lower interceptor inventories reduce the margin available for responding to another major missile threat while production catches up.

At the same time, the Pentagon says it is working to accelerate procurement and expand production capacity.

Key figures

The bottom line

The Pentagon inspector general’s report provides the clearest official confirmation so far that the Iran conflict has drawn down U.S. munitions inventories and exposed weaknesses in the capacity to rapidly replace some advanced weapons.

It does not establish that the U.S. military is incapable of continuing operations. Instead, it documents a different problem: the gap between wartime consumption and the speed at which the defense industry can rebuild certain inventories.

The Pentagon’s challenge now is to replenish those stocks while maintaining current military commitments and addressing the industrial bottlenecks identified by its own watchdog.

Source documents: The primary reference for this report is the Department of War Office of Inspector General’s Operation Epic Fury Lead Inspector General report to Congress, covering the period through June 30, 2026. Official Pentagon Inspector General report The Congressional Budget Office’s subsequent cost assessment was published September 15, 2026. Congressional Budget Office — Estimating the Cost of Combat Operations Against Iran

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