U.S. Defense Secretary Ash Carter smiles as U.S. Air Force Gen. Philip M. Breedlove, NATO’s supreme allied commander for Europe and commander of U.S. European Command, introduces him during a high-level meeting with regional defense leaders in Stuttgart, Germany, June 5, 2015. Carter's visit to Germany was the last stop on a 10-day trip, which also included meetings with leaders and troops in Hawaii, Singapore, Vietnam and India.