US Defense Chief: 'Lasting Defeat' Needed Against Islamic State

U.S. Defense Secretary Ashton Carter gathers top U.S. military commanders and diplomats for talks on the battle against the Islamic State, at Camp Arifjan, Kuwait, Feb. 23, 2015.

U.S. Defense Secretary Ashton Carter arrives for a regional security meeting at Camp Arifjan, Kuwait, Feb. 23, 2015.

U.S. Defense Secretary Ashton Carter delivers a speech to troops at Camp Arifjan, Kuwait, Feb. 23, 2015.

U.S. Defense Secretary Ashton Carter is greeted by Kuwaiti Defense Minister Sheikh Khalid al-Jarrah al-Sabah upon his arrival at Kuwait City International Airport, Kuwait, Feb. 22, 2015.

Defense Secretary Ashton Carter speaks with U.S. military personnel at Kandahar Airfield in Afghanistan, Feb. 22, 2015.

U.S. Defense Secretary Ashton Carter listens to remarks by Afghan President Ashraf Ghani during a news conference at the Presidential Palace in Kabul, Feb. 21, 2015.