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.
New figures released by the Defense Department provide the first detailed breakdown of costs associated with what has mainly been an air war against ISIS. Daily flight operations have cost $1.501 billion -- or 55 percent of the total amount of $2.74 billion. Both the Air Force and Navy conduct airstrikes in Iraq and Syria, but Air Force costs make up 67 percent of the $2.74 billion spent so far, according to the figures released. A similar percentage is reflected in the average daily cost, where Air Force costs make up $6.1 million of the $9.1 million spent daily. The figures also show that $646 million has been spent on the munitions used against ISIS. The American strategy against ISIS also includes missions to train the Iraqi military and moderate Syrian rebels.