CSIS calculated that Operation Epic Fury costs the United States nearly $900 million per day1 — consistent with the centre's earlier estimate of $16.5 billion over the war's first 12 days. The daily rate has stabilised as initial deployment surges give way to sustained operational expenditure: munitions, fuel, air defence interceptors, and force protection across a theatre from the eastern Mediterranean to The Persian Gulf.
The International Institute for Strategic Studies described the conflict as at risk of becoming a "battle of endurance"2. Israel entered with depleted interceptor stocks from the Twelve-Day War; Arrow and David's Sling rounds cost $2–3 million each, and at Iran's firing rate of seven salvos in a single night, Israel's NIS 2.6 billion emergency procurement buys time but not resolution. The IRGC's claim that most missiles fired were produced "a decade ago" — if true — implies newer stocks remain in reserve. Endurance favours the side that can sustain expenditure relative to its resources — a different calculus for a $28 trillion economy burning $900 million a day than for a $400 billion economy absorbing infrastructure destruction it cannot quickly replace.
Chatham House assessed that if fighting persists for months, Brent Crude could reach $130 per barrel and the Eurozone would "probably" contract in Q23. Brent closed at $100.21 on 17 March — 49% above the pre-war $67.41, with Gulf production down at least 10 million barrels per day in what the IEA called "the largest supply disruption in the history of the global oil market". US diesel has hit $5 per gallon, up 34% since 28 February, and gasoline $3.79 — prices that feed directly into household budgets and freight costs before second-order inflation effects propagate through supply chains.
