U.S. Secretary of Defense Ash Carter speaks at the IISS Shangri-La Dialogue in Singapore June 4, 2016. REUTERS/Edgar Su

U.S. Secretary of Defense Ash Carter speaks at the IISS Shangri-La Dialogue in Singapore June 4, 2016. REUTERS/Edgar Su

U.S. Secretary of Defense Ash Carter speaks at the IISS Shangri-La Dialogue in Singapore June 4, 2016. REUTERS/Edgar Su

June 4, 2016 12:23 AM (UTC+8)