Commander warns against leaving Afghanistan too rapidly

The battle-hardened Army commander nominated to take over U.S. military operations in Afghanistan warns Congress that if America leaves the fight too rapidly, there is a risk Islamic State militants could merge with al-Qaida and plan attacks against the U.S. Lt. Gen. Scott Miller, a former Army Delta commando who heads U.S. Joint Special Operations Command, tells the Senate Armed Services Committee that, if confirmed, he'll reassess the troop numbers in Afghanistan to see if the force size is right.