Airport Traveling Gripes

In a week and a half, I will be heading back home by airplane for the Thanksgiving holidays. Thus, I will have to deal with all the truly ridiculous "security" measures at the airport that are being talked about today.
(Side note: there's a really nice xkcd comic about this as well, discussing how inconsistent it is to confiscate small liquid containers yet allow laptop batteries to go through.)
Anyway, there seems to be a real backlash (Derek Kravitz, Washington Post) against the new super-restrictive rules regarding full-body frisks and scanners; while before, when new restrictions were put in place, people would grudgingly accept them and move on, now most people think these particular rules cross the line of decent and sane security measures into the realm of indecency and violation of rights.
There are a couple of things I don't get about this (the new frisking measures, not the backlash). It seems like this was prompted by a plot to blow up a cargo plane. Does anyone else see anything wrong with this? OK, I'll say it: why should a plot to sneak explosives onto a cargo plane and detonate them remotely lead to restrictions allowing security officials to pat you down fully on passenger planes? There seems to be no cause-effect connection at all here; it just seems totally arbitrary.
Furthermore, the numerous quotes of passengers describing these new rules as the TSA treating passengers like criminals isn't hyperbole by any means; an analyst at a security consultancy in Oregon has described the new procedures as "the same frisking that police use with probable cause". This is more serious than "reasonable suspicion"; this means that the TSA has a strong feeling that every single traveler is probably a terrorist. Hence, I will also say this to the TSA: stop treating us like criminals! What ever happened to the presumption of innocence?
Finally, why is it OK for the government to be violating people like this? I remember learning in a set of videos required by my college over the summer that "unless there's consent, it's assault". Does that mean they're technically sexually assaulting us all? Or are they going to pull the excuse of "by flying, you are automatically consenting to all of our procedures"?