Cmdr. James B. Wallace, former commanding officer of Coast Guard Port Security Unit 307, a Reserve unit home-ported in Clearwater, Fla., says farewell to his crew during his speech at a change of ceremony at Air Station Clearwater, Aug. 17, 2013. A change of command is a military tradition that represents a formal transfer of authority and responsibility from one commanding officer to another. (U.S. Coast Guard photo by Petty Officer 2nd Class Michael De Nyse)