ABC News’ David Muir gets exclusive access on USS Florida

The nuclear-powered, U.S. Navy guided-missile submarine has 160 crew members on board and was in the Mediterranean, preparing for a highly classified mission. WATCH THE FULL EPISODE OF ’WORLD NEWS TONIGHT’: WATCH OTHER FULL EPISODES OF WORLD NEWS TONIGHT: #WorldNewsTonight #DavidMuir #USSFlorida #Navy #Submarine