Perhaps if the security checks were pared to the useful, with all the window dressing removed, we'd all feel happier because there would at least be understandable reasons for the checks. The liquids one is so easy to circumvent unless you ban all liquids for everyone, that it might as well not be there unless you're going to analyse the contents of each container. some of the "sharp" implements are no more dangerous than the free pens provided on some flights. There are other things allowed on flights that are probably far more dangerous, but this is probably not the place to bring them up.