OK. A lot to respond to, so here goes:
I don't believe the 'water terrorists' in the UK were dry running (bad pun). But I do think that there are some domestic intel gatherers operating to a limited degree, and looking for weak spots to maybe exploit later.
It's true, the water ban has nothing to do with anything except showing the American people 'Look, we're doing something about the new threat'. I really wish the media had just kept this whole darn incident quiet, and let the police in the UK get at these people on their own.
Think back pre-9/11. How were the security checkpoints any different then (water / gel bans excluded)? They really weren't. Box cutters and other small cutting articles were allowed, but that is really the only security screening difference I see. Now those articles are prohibited (as they should have been in the first place). Taking off the shoes is a pain in the rear end, but it is easy enough. Granted, I am also a healthy person, so bending over and taking them off is no big deal to me. I know for others that it isn't.
As others have posted, there have been several good steps taken, without the need for overkill. Got it. And for the most part, I agree.
Wally Bird, I'd have to break out the Poor Man's James Bond and see if there are any kind of explosives that can be made in that manner. I know that Bleach can be mixed with other substances for some pretty nasty gaseous effects; I'm not sure about explosives. I don't know if gasoline or rubbing alcohol smuggled in a plastic water bottle would melt the bottle, or if enough could be brought in to do damage, but it could start a nasty fire on board, causing panic and other mayhem. I would say that you could probably fashion Det cord into shoelaces, but the explosive sniffers would probably catch that. I guess that a toothpaste tube could theoretically be filled with C4 or PETN or RDX or some other nasty explosive compound.
Now, is it enough of a worry to ban all of these common articles? Not to me, but how about the average American voter? I don't mind checking this stuff, if only the airlines could get it back to the luggage carosel quickly after the flight. And some airports are better at this than others.