World War II is widely rememberd as the most expensive war ever fought by the United States. In constant dollars, World War II's portion of our nation's GDP reached 35.8% at its height, and ultimately cost a staggering $4.1 trillion in FY2011 dollars. Many have long thought that, short of a feared WWIII, it would hardly be likely that today's unconventional wars could approach such costs. However, a recent report has found that, when it is all said and done, the war in Iraq will end up costing more, in constant FY2011 dollars, than even WWII.
