Bruce Schneier's article in Wired News, Refuse to be Terrorized, clearly conveys a message I've long advocated: any reaction to terrorist threats that degrades individual and collective liberties is simply aiding the terrorists' objectives.
The point of terrorism is to cause terror, sometimes to further a political goal and sometimes out of sheer hatred. The people terrorists kill are not the targets; they are collateral damage. And blowing up planes, trains, markets or buses is not the goal; those are just tactics.The real targets of terrorism are the rest of us: the billions of us who are not killed but are terrorized because of the killing. The real point of terrorism is not the act itself, but our reaction to the act.
And we're doing exactly what the terrorists want.

I have several comments, I'll try to make them all in as few words as possible.
I agree that a good number of the inconveniences related to air travel these days are nothing more than lip service, to make the flying public feel that something is being done. However, that's not to say that a "just get on the plane and don't worry" attitude is correct either.
Looking only at the examples provided (I'm using Schneier's descriptions as I haven't read each article, but even if he didn't accurately describe one, none of his descriptions are so outlandish that it could be said "that'll never happen")
All in all, I think I can sum up my thoughts pretty simply : "Err on the side of caution = Good. Extreme paranoia = bad". I'm OK with a delay caused by the powers that be wanting to double check a positive reading they got on an explosive test. I'm not OK with having to land the plane because the bathroom door was locked. I'm OK with an emergency landing caused by a direct bomb threat being found on the plane. I'm not OK with an emergency landing caused by the fact that someone brought an illicit waterbottle on the plane.
The terrorists haven't won if they have caused us to be more cautious and more careful about how we go about our lives, they've won if they've launched us into a paranoia spiral that ends up with us having to be sedated, stripped, and strapped to beds, before being loaded onto airplanes.
Hal, I think you and Schneier agree for the most part. I believe that his primary criticism wasn't taking precautionary action, it was the oversensationalistic actions of both the media and politicians to use these false positives and related non-events to scare us into either (a) tuning into the news more often, or (b) voting for the candidate that's "toughest on terror," neither of which is a healthy or helpful way to react.
I know he and I aren't too far off, but reading only that one article isn't enough to see that (although reading every link contained may be). I just didn't like how he didn't seperate the "OK, this is the system working properly" from the "WTF?!" in the examples he gave.
That is, what I consider "the system working properly" :)
Bruce rocks. I loved his book, Secrets and Lies.