Unfortunate incident, but this is what happens when there is no security plan in force. Obviously there will be military personnel with various levels of training and specialties on any base or military center. That is why there should be a trained security team in place to secure the premises. When people feel their lives are in danger, they will act on their own.
I think the DOD needs to have a warning system via mobile to all recruiters. There never should have been a second shooting.