Defense Secretary Jim Mattis will travel west this week to Washington and California, where he will visit the Defense Innovation Unit Experimental and seek to strengthen ties with technology companies in Silicon Valley, according to a Pentagon spokesman. This week's trip marks Mattis' first official visit to DIUx, according to Navy Capt. Jeff Davis. Mattis is expected to meet with DIUx staff, as well as leaders in Silicon Valley's technology community to determine how the Defense Department "can leverage new...