The US Department of Defense’s Inspector General has acknowledged that the war with Iran placed significant pressure on American weapons stocks, resulting in strategic munitions shortfalls and exposing bottlenecks in the country’s defence production capacity.
The assessment was included in the first Pentagon Inspector General’s report examining the US-Israeli war on Iran. Released on Monday, the report provides an account of the campaign’s financial cost, physical damage and impact on US military inventories.
More than 50,000 US service members participated in the campaign, carrying out thousands of combat missions and using an estimated $22.3 billion worth of munitions, according to the report.
The report, which covers the period from February 28 to June 30, puts the direct cost of the conflict at approximately $33.4 billion. Munitions accounted for $22.3bn, while equipment losses amounted to $3.7bn and other expenditures totalled $7.4bn.
The figure does not include the costs of repairing damaged facilities, replacing aircraft or replenishing critical weapons stocks, meaning the overall financial burden of the conflict could be considerably higher.
US officials have previously provided different estimates of the war’s cost. In late July, Defence Secretary Pete Hegseth told Congress that the Pentagon had spent around $37.5bn on the conflict. Separately, US media reports cited officials and people familiar with internal estimates as putting the eventual cost at between $80bn and $100bn.
The higher estimates appear to have included expenses not covered by the Inspector General’s four-month assessment, such as infrastructure repairs, aircraft replacement and replenishment of weapons.
The Inspector General’s findings also confirmed concerns that had emerged during the conflict over the rapid depletion of US munitions. The report said the campaign “resulted in strategic inventory shortfalls and revealed industrial base bottlenecks for munitions resupply”.
Earlier reports had raised concerns about declining stocks of precision weapons as the US intensified its operations against Iranian targets. In March, US military forces were reported to have fired more than 850 Tomahawk cruise missiles during the first four weeks of the conflict, raising concerns among some Pentagon officials about the pace at which precision weapons were being consumed.
At the time, the White House and Pentagon maintained that the United States had sufficient weapons stocks to sustain the operation.
By late April, Pentagon officials estimated that the first two months of the campaign had cost about $25bn, with munitions accounting for the bulk of the expenditure. Analysts, however, questioned whether the estimate fully reflected equipment losses, damage to military bases and other related costs.
The latest Inspector General’s assessment represents an official acknowledgement that the campaign placed considerable pressure on US weapons inventories.
The Pentagon said it was responding by accelerating procurement and production timelines and building reserves of critical materials, components and selected munitions to improve its ability to respond to future conflicts.
The conflict also caused significant damage to US military infrastructure across the region.
According to the report, Iranian attacks damaged or destroyed hundreds of buildings and other structures at US bases in Kuwait, Bahrain, Qatar, the United Arab Emirates, Saudi Arabia, Iraq, Oman and Jordan. Dozens of US aircraft and drones were also damaged or destroyed.
The assessment confirmed that Iran targeted the US Navy’s main logistics hub in Bahrain with drones and ballistic missiles. At least 30 large US drones were destroyed during the period covered by the report.
US diplomatic facilities were also affected. American diplomatic properties in Iraq, Kuwait, Saudi Arabia and the UAE sustained an estimated $184 million in physical damage, while the State Department reported an additional $113m in conflict-related costs, including nearly $80m for contingency planning and evacuations.
More than 20,000 US military and diplomatic personnel were displaced during the conflict, according to the assessment.
The findings highlight the broader impact of Operation Epic Fury, showing that the campaign not only consumed large quantities of American weapons but also placed pressure on the US defence industry’s ability to replenish stocks, protect military installations and relocate personnel and equipment from threatened facilities.
