Which is where I got the idea? for the hair pin? On planes I carry a book of Suduko puzzles and several sharp # 2 lead pencils. But, I have also got on a plane carry a 32" diamond willow stick. I find it hilarious because someone could do a lot more damage with a big stick or a couple small sharp ones than with a 2 1/2 pocket knife
But, then I find the whole airport security thing really stupid. Might be a lot harder to get on a plane and blow yourself and it up, but any suicide bomber with 2 brain cells could get in the security lane of a busy airport and wait till he was right in the middle of of all the bunched up people before he pushed the button.
Plus there is no need to hijack a plane, a nation that financed terrorism now has a nice base to fly super sonic fighters full of fuel from in Mountain Home Idaho, just a few hundred miles from Seattle, Denver and Salt Lake City