The Center for Strategic and International Studies (CSIS), a US-based research institute, published an analysis on 5/3 indicating that Washington spent approximately USD 3.7 billion during the first 100 hours of its offensive against Iran. This equates to USD 891 million per day, a period often considered the most intense phase of airstrikes.

This total includes about USD 196 million in operational costs for forces, a significant portion of which was already allocated in the fiscal year 2026 defense budget. Additionally, munitions replenishment costs were around USD 3.1 billion, while equipment damage and infrastructure restoration amounted to about USD 350 million, largely unfunded by the existing budget.

Air combat operations account for a substantial part of the overall expenditure. CSIS estimates that in the initial 100 hours, the US military spent around USD 125 million on aircraft sorties from ground bases, with an expected additional cost of at least USD 30 million daily thereafter.

Currently, 200 US military aircraft are engaged in the Middle East. This includes F-22 stealth fighter jets, F-35 fighter jets, F-15E heavy fighter jets, F-16 light fighter jets, and A-10 attack aircraft.

The US Navy has also deployed a large force to the Middle East, comprising two aircraft carriers, 14 destroyers, and three littoral combat ships. Operational costs for the US fleet in the Middle East were approximately USD 64.5 million during the first four days, followed by USD 15 million daily.

The US military used over 2,000 weapons to strike targets in Iran during the initial 100 hours. CSIS estimates that each target received an average of 1.3 weapons, with munitions consumption potentially reaching 2,600 units. Replenishing these expended weapons could cost around USD 1.5 billion.

The costs for intercepting Iranian ballistic missiles and unmanned aerial vehicles (UAVs) are also significant. Tehran launched approximately 500 missiles and 2,000 UAVs, with the US primarily assigning interception tasks to its Patriot and THAAD air defense systems. According to CSIS, replenishing munitions for these systems would require about USD 1.7 billion.

Confirmed US equipment damage has been relatively limited thus far. The most notable incident involved three F-15E Strike Eagle fighter jets accidentally shot down over Kuwaiti airspace. The F-15E production line has ceased, transitioning to the advanced F-15EX variant. To replace the three Strike Eagles, the US military would need to spend USD 309 million to acquire new F-15EX aircraft.

Several US military facilities in Kuwait and Qatar also sustained damage from Iranian attacks. Repairing these facilities would require at least USD 50 million from the US.

Experts at CSIS assess that US costs could slow down after the most intense initial phase of the conflict. The level of expenditure depends on whether the US shifts to using less costly weapons, as well as the intensity and effectiveness of Iran's retaliatory strikes.

However, most of the campaign's expenses have not been included in the current defense budget, necessitating additional funding from the US government. CSIS indicates that the Pentagon will likely request supplementary or adjusted appropriations from Congress to cover these costs.

The US and Israel launched an air campaign against Iran on 28/2, resulting in the deaths of numerous senior military and political commanders, including Supreme Leader Ali Khamenei. This ignited intense retaliation from Tehran against Israeli territory and US bases in the Middle East.

The conflict shows no signs of de-escalation, as the US has urged Israel to continue the fight "to the end" with Iran, while Tehran vows to conclude only after "inflicting a heavy blow" on the US.

Nguyen Tien (According to CNN, AP, AFP)