The issue of screening all or none (baggage handlers, engineers etc) is no doubt a cost one. One that would be resolved overnight if an attack happened via these means. It's a totally reactive system and the politicians do what they need to do to avoid spending where they can. For them it's purely about staying in power nothing more nothing less.
I've always said "you screen everyone or you screen no one."
Here's the kicker: what if the current intelligence forces don't pick up 100% of the threats? All you need is 1% to get through and it's all over red rover. In the face of this, the encrypted software needs to go.
A National ID card and DNA register would solve a lot of problems and crimes but also create a lot of problems and be a massive loss of privacy.
I don't have a problem with it as I've got nothing to hide. Having said that, I can see very much how it could become a problem (the point sunfish makes).
Pilot A has been in the industry for 15 years with an unblemished record but is related to someone who is being watched by the authorities. Now what? Ultimately being related doesn't mean you are connected (quite the opposite in some families!). There are people at the airport today that are in this very situation.
I think the encryption issue is probably the quickest least expensive way to trap most of the problems and the government to its credit is trying on this front.
Spare a thought for the guys at security most of which are just doing a job. It would have to be the worst job, next to parking inspector, that I I could think of.
If we want maximum protection then we have to give into the screening and the loss civil liberties. In ways you have to wonder if it's really worth it as its being pointed out that there is no 100% fool proof system.