When Congress passed the Authorization for the Use of Military Force immediately after the 9/11 attacks, no one could have imagined this authorization would continue to be the basis for American wars that persist a decade and a half later.

More than a decade and half after 9/11, U.S. military actions in countries such as Syria, Iraq and Afghanistan and several other Muslim nations are governed by the Authorization for the Use of Military Force (AUMF) that was passed in the days immediately after 9/11.

Every decision to use military force is an excruciatingly difficult one.

A decade and a half ago, the U.S. Air Force dropped massive 15,000-pound 'Daisy Cutter' bombs on the Tora Bora complex where Osama bin Laden was hiding in December 2001.

If the use of military force, or the threat of use of military force, is necessary to bring about a political solution, NATO is prepared to do it,

On a number of occasions, military operations which involved
excessive use of force and other violations, haven't
necessarily been addressed,