U.S. Defense Secretary Ash Carter answers questions during a joint press conference with U.K. Defense Secretary Michael Fallon at the U.K. Defense Ministry in London, Oct. 9, 2015. Carter is on a five-day trip to Europe to attend the NATO Defense Ministerial Conference in Brussels and to meet with counterparts in Spain, Italy, and the United Kingdom. DoD photo by U.S. Army Sgt. 1st Class Clydell Kinchen