USS Nitze (DDG 94) sails off the coast of Key West, Fla., Nov. 9, 2011, during Exercise Vigilant Shield 12. The exercise in Key West is the "first-ever proof of concept" for the military's Joint Deployable Integrated Air and Missile Defense System, a collection of high-end radars and missile systems as well as aircraft that work in tandem in the event of a threat to the continental United States. (U.S. Air Force photo by Staff Sgt. Kamaile O. Long/Released)