After 9/11 they wouldn't let you take anything sharp onto an airline. Sure.
After the shoe bomber got caught you had to take your shoes off for inspection. Ok.
Some terrorist in Britain came up with a fairly half-baked plan to smuggle explosives hidden as household liquids. Now we restrict the size of liquids that you can take on a flight. Ummm, Really?
And now this. Which means the obvious countermeasure is...oh boy.