Marines assigned to the 11th Marine Expeditionary Unit (MEU) man a .50-caliber machine gun to practice security measures while a rigid hull inflatable boat (RHIB) performs simulated fast attack craft exercises during a general quarters drill aboard amphibious transport dock ship USS San Diego (LPD 22). San Diego is a part of the Makin Island Amphibious Ready Group and, with the embarked 11th MEU, maintains its readiness to promote long-term regional security by conducting regularly scheduled, recurring exercises in the U.S. 5th Fleet area of responsibility. (U.S. Navy photo by Mass Communication Specialist 3rd Class Gerald Dudley Reynolds/Released)