Don't worry about 9/11. The military knows that terrorists don't request
practice approaches.

You are supposed to have at least a written description of the approach.

Some military bases are more accomodating than others; it never hurts to
ask. It does not help to put anything in the remarks. If the base does PAR
approaches, they will have the staffing for it whether you call ahead or
not. The only issues are the local base policy (base commanders tend to be
more worried about liability than terrorism) and workload.