U.S. Defense Secretary Mattis and Vietnamese Defense Minister Gen. Ngo Xuan Lich listen to national anthems during an honor cordon at the Pentagon in Arlington

U.S. Defense Secretary Mattis and Vietnamese Defense Minister Gen. Ngo Xuan Lich listen to national anthems during an honor cordon at the Pentagon in Arlington

U.S. Defense Secretary Jim Mattis (L) and Vietnamese Defense Minister Gen. Ngo Xuan Lich listen to national anthems during an honor cordon at the Pentagon in Arlington, Virginia, U.S., August 8, 2017. REUTERS/Kevin Lamarque

August 16, 2017 5:56 PM (UTC+8)