“The first six days of war in Iran cost U.S. taxpayers at least $11.3 billion in munitions alone, according to Pentagon estimates reviewed by lawmakers, and experts say the ongoing cost could increase exponentially. That total does not include the cost of operating and maintaining the military force engaged in the war or battle damage sustained from Iran’s attacks.
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While initial cost estimates of the U.S. wars in Iraq and Afghanistan were around $50 to $60 billion, they ended up costing a combined $8 trillion, according to analysis by Costs of War.”
https://www.yahoo.com/news/articles/much-iran-war-costing-taxpayers-212311982.html