Casualty of War: US Economy:
"The wars in Iraq and Afghanistan have already cost taxpayers $314 billion, and the Congressional Budget Office projects additional expenses of perhaps $450 billion over the next 10 years.
That could make the combined campaigns, especially the war in Iraq, the most expensive military effort in the last 60 years, causing even some conservative experts to criticize the open-ended commitment to an elusive goal. The concern is that the soaring costs, given little weight before now, could play a growing role in U.S. strategic decisions because of the fiscal impact."
Pretty soon you're talking about real money here...