You seem quite proud of the fact that you repeatedly, and illegally, smuggle a lethal weapon onto an aircraft.
Do you realise one can strangle another with ones bare hands?
Or hit and kick till the other is dead?
So let's dismember all passengers upon boarding
Let's accept that there is a tiny tiny risk that one runs into a madman... I appreciate it when organized armed criminals are kept off the plane, before metal detectors were common there were too many hijackings to my taste. When there is one unruly passenger, there are enough "sane" people on board to subdue him, as long as he does not carry incapacitating arms.
PAXboy: My estimate is that small knives get past screening in more than 50% of the cases. Experienced "red team" security testers routinely claim getting more than 50% of their guns through the check.