CNBC: America has spent $6.4 trillion on wars in the Middle East and Asia since 2001, a new study says. Another 21 million people have been displaced due to violence. The post-9/11 wars in Iraq, Afghanistan, Pakistan and Syria have expanded to more than 80 countries.

* The U.S. wars in Afghanistan, Iraq, Syria and Pakistan have cost American taxpayers $6.4 trillion since they began in 2001.

* That total is $2 trillion more than all federal government spending during the recently completed fiscal year.

* The report, from Watson Institute of International and Public Affairs at Brown University, also finds that more than 801,000 people have died as a direct result of fighting.