Overseas wars have cost US $4.3 trillion since 2001
November 9, 2017 The Hill
An article in The Hill cites the Costs of War Project's study on the U.S. budgetary costs of war since 9/11. "Study author Neta Crawford notes that combat operations since 2001 'have been largely paid for by borrowing, part of the reason the U.S. went from budget surplus to deficits after 2001.""