Congress has not formally authorized hostilities in Iran, yet the administration may soon seek emergency funding for a campaign with no publicly defined duration or full cost. Defense briefings to lawmakers, obtained by a congressional aide speaking on background, said the Pentagon spent roughly $5.6 billion on munitions in the first two days of the operation — identified in some briefings as Operation Epic Fury — and that total munitions spending has likely climbed into double digits since.
The White House and Office of Management and Budget have not provided a public accounting of current or projected expenses. A Defense Department spokesperson said there was nothing to release, while House Democrats have asked the Congressional Budget Office to produce independent estimates. Lawmakers face a political split: Republicans controlling Congress have defended the administration’s authority to act, while Democrats sought — unsuccessfully so far — to require prior congressional authorization and would be needed to pass any larger supplemental spending through the Senate.
Defense analysts warn the visible costs so far are only a fraction of what a longer campaign or a shift to ground operations would require. Michael O’Hanlon of the Brookings Institution notes that a typical extended air campaign might cost a few billion dollars per month, but current operations appear to be burning munitions at a pace closer to billions per week. If regime change or occupation is attempted, the financial and human bills would expand dramatically: historical calculations from Afghanistan and Iraq show an average of about $1 million per deployed U.S. troop per year once infrastructure, equipment, health care and related support are included. Where 100,000 to 175,000 troops were once deployed in those wars, an occupation of Iran could conceivably require a quarter-million or more, translating into roughly $250 billion to $300 billion for a single year of presence — before accounting for follow-on costs.
Beyond direct budgetary outlays, the wider economic and diplomatic fallout could be substantial: damage to U.S. facilities overseas, higher global energy prices, disruptions to fertilizer production and agriculture, and long-term instability in the region. The human toll is also uncertain and likely to grow. Seven U.S. service members have died so far; analysts point to the first Gulf War and the long wars in Afghanistan and Iraq as reminders that battlefield fatalities and indirect deaths from shortages of water, food and medical care can mount over years.
Experts are skeptical that air and naval strikes alone can topple or replace a government. Seth Jones of the Center for Strategic and International Studies argues it would be “very difficult” to inflict decisive damage on the Iranian regime without ground forces. Past interventions in Afghanistan, Iraq and Libya combined airpower with boots on the ground and produced prolonged instability, insurgencies or civil conflict. Analysts warn that calls for popular uprisings without protection risk reprisals against civilians, citing historical examples.
Sustaining intensive operations also strains U.S. stockpiles and readiness for other contingencies. Some missile-defense and offensive systems saw significant drawdowns in 2025, and heavy use now could deplete munitions needed for planning around China, North Korea or Russia. The U.S. already has an $838.7 billion defense budget for 2026, plus about $150 billion enacted in 2025 for specific programs, but those resources are finite and reallocating them to a new, protracted campaign would be costly and politically fraught.
There is also a risk of escalation and regional widening. Iran’s partners and proxies could attack U.S. forces or civilians abroad — analysts point to potential Houthi strikes from Yemen, actions by Iraqi Shiite militias in Syria or Iraq, or operations by the IRGC and allied groups. Such blowback could expand the scope and expense of the conflict.
With no public estimate from the administration and multiple unknowns about objectives and timelines, Congress and the public lack a clear picture of the financial and human commitments ahead. History shows that wars billed as brief or limited can become prolonged, expensive and destabilizing, producing consequences that last far beyond initial operations.
