As such, comparative advantage is an important concept in global trade, and it's the reason many countries concentrate on trying to produce certain goods or services more efficiently than other countries.
In March 2013, the total cost of the Iraq War to date was estimated at $1.7 trillion by the Watson Institute of International Studies at Brown University. Some argue that the total cost of the war to the U.S. economy will range from $3 trillion to $6 trillion, including interest rates, by 2053, as described in the Watson Institute's report.
The effort was supposed to be cheap -- to require few troops and even less time. Instead, it cost the United States $800 billion at least, thousands of lives and nearly nine grueling years (see the graphic below for a further breakdown of various costs). The toll on the people of Iraq were even greater.