The first Zumwalt-class destroyer, USS Zumwalt, the largest ever built for the U.S. Navy, passes spectators at Fort Popham at the mouth of the Kennebec River in Phibbsburg, Maine, Monday, Dec. 7, 2015, in Bath, Maine. The ship is headed out to sea for the first time to undergo sea trials. (AP Photo/Robert F. Bukaty)