>"In your world, without TSA or similar authority, plane hijacking wouldn't become a regular weekly occurrence?"

I think the answer lies in your phrase "similar authority." One idea is to privatize this job. The TSA culture is a joke. This is an agency who have failed to understand that their mandate is to protect people and that they are there to serve. Instead they treat flying public like adversaries while browbeating and infantilizing them. They seem to imagine that their mandate is to stress people out and confiscate toothpaste. It's hard to imagine a ruder public agency. Not all of course as sometimes you do get nice folks who understand they are there to serve. This is generally the exception though. It's so exceptional that when it does happen it's kind of shocking.