BS: You don't have a responsibility to screen shoes; you have one to protect air travel from terrorism to the best of your ability. You're picking and choosing. We know the Chechnyan terrorists who downed two Russian planes in 2004 got through security partly because different people carried the explosive and the detonator. Why doesn't this count as a continued, active attack method?Link
I don't want to even think about how much C4 I can strap to my legs and walk through your magnetometers. Or search the Internet for "BeerBelly." It's a device you can strap to your chest to smuggle beer into stadiums, but you can also use it smuggle 40 ounces of dangerous liquid explosive onto planes. The magnetometer won't detect it. Your secondary screening wandings won't detect it. Why aren't you making us all take our shirts off? Will you have to find a printout of the webpage in some terrorist safe house? Or will someone actually have to try it? If that doesn't bother you, search the Internet for "cell phone gun."
It's "cover your ass" security. If someone tries to blow up a plane with a shoe or a liquid, you'll take a lot of blame for not catching it. But if someone uses any of these other, equally known, attack methods, you'll be blamed less because they're less public.
I write books. My latest is a YA science fiction novel called Homeland (it's the sequel to Little Brother). More books: Rapture of the Nerds (a novel, with Charlie Stross); With a Little Help (short stories); and The Great Big Beautiful Tomorrow (novella and nonfic). I speak all over the place and I tweet and tumble, too.