Pictures like that make me smile.
USAF aircraft, typically launched from nearby Patrick Air Force Base, provide security cover for all NASA and DoD launches out of Kennedy Space Center and Cape Canaveral Air Force Station. They have been doing this ever since the early days of the space program. The Navy performs a similar job on the ocean surface downrange from the launch facility. Their primary responsibility is to provide security for the launch and pre- and post-launch operations. Usually this involves making sure that private aircraft and boats trying to sight-see the launch do not get too close and become a hazard for launch operations. There have been a few occasions in the past where an unauthorized airplane or boat wanders in to the restricted area just at the wrong time, and a launch has to be postponed while the range is cleared (this happened during one of the Mars Rover launch attempts, when a guy participating in a fishing tournament crossed the line from the tournament area into the launch exclusion zone). These USAF and USN folks try very hard to make sure that does not happen, as scrubbing a launch can be a VERY expensive thing to do.
-dave
.