You get in the airport security line, throw away your bottle of water, unpack everything in your carry-on, pull off your shoes, your jacket, your scarf.
You walk through the metal detector, setting off a screeching beep. You go back, take off your watch, empty your pockets, slip off your belt. You still beep. You get wanded, they rifle through your bag. Turns out it was a foil gum-wrapper.
You're frustrated, you're late, you're embarrassed. Is anyone any safer?
[S]ome critics question whether practices such as stripping off shoes and tossing water bottles is more theater than security. Even those who agree with the shoe and liquid routine believe there are still important holes in security, like the failure to inspect all cargo or to screen all airport employees with access to planes.