U.S. Marines with the Ground Combat Element, Special-Purpose Marine Air-Ground Task Force Crisis Response-Africa conduct an alert-force drill aboard Naval Station Rota, Spain. SPMAGTF-CR-AF is a self-sustaining crisis-response force prepared for the protection of American personnel and facilities on the African continent when directed by U.S. Africa Command. (U.S. Marine Corps photo by Sgt. Tia Nagle)