I was working on the Acadamy in CO Springs this summer. They had civilians at the gate with side arms and AF people at the entrance to the cadet area with M-4s. Very cool place to work.
I was working at the enlisted mens club one afternoon and the big boss walked in and told me to hit the big red button under the counter for a drill. This was the emergency button. In about 30 seconds, the first Air Police started piling in with M-16s - They did not know it was a drill until they arrived.
I'm quite sure that most every facility on a base has an emergency button that gets real fast response although like I said, this was quite a few years ago for me. I'd be flat pissed off if this kind of alert network and security training were to have diminished from what it was then.