"questions about security at these smaller regional airports..."
I seem to recall a jeep driving through a fence and running crazy at another, not quite so small regional airport. Unless they put up 12 foot concrete walls around airports and eliminate all foot traffic, some clown will make it through.
It isn't the security. It's the crazy people who are not cared for. Better mental health treatment, and handling it as a desease rather than a mental issue would go along way to fix the ever increasing problem.