`` One problem is how to separate costs of military operations from costs of forces in peacetime . `` War on terrorism '' is second most-expensive war in U.S. history , report says . Adjusted for inflation , the American Revolution cost $ 2.4 trillion . The cost of the wars in Afghanistan and Iraq could total more than $ 4 trillion by the 1940s .
`` War on terrorism '' is second most-expensive war in U.S. history , report says . Adjusted for inflation , the American Revolution cost $ 2.4 trillion . The cost of the wars in Afghanistan and Iraq could total more than $ 4 trillion by the 1940s .