When it becomes an everyday thing, then we'll talk about arming everyone on base.
Well, this is twice in very recent memory.
Most people don't remember this incident from Camp Liberty Iraq, but it does help to prove A4's point that the people that do this kind of thing are "crazy", but still sane enough to attack people that they know will not be armed.
OBTW, the guy who did the shooting in this case has been declared incompetent to stand trial.
Then there was this incident, while off-base, the soldiers would have benefited from being armed:
Muslim murders Army recruiter in Arkansas.