If those full-body scanners are such a good idea and not a threat to privacy, then why are all the demonstration photos we're seeing of men (particularly ugly one here)?
Why not a woman or a twelve-year-old girl?
We're not supposed to be worried about any threat to privacy or our concept of decency in the service of security, after all.
Update: After I wrote the above, it occurred to me that most of the commentary I'm seeing from ordinary people - letters to the editor and comments on news articles and blogs - is taking the underpants bomber in stride. It's the security consultants and others who might make a buck from, er, enhanced security, who seem to be most insistent that any and all means must be used to make sure that terrorists never, ever, ever get on a plane. Well, any and all scanning devices. This convinced me it was worth saying. Michael Chertoff should be ashamed of himself, as should Fred Hiatt.