Okay. Military weapons knowledge isn't my forte, and that's one of the many reasons I'm just a pizza delivery man.
I don't suppose there are explosives more powerful that could in fact be threatening to life or limb? The 9/11 hijackings were carried out with box cutters, iirc. Threatening to literally blow someone's head to pieces right in front of everyone could be more than a little coercive, if people were afraid of rushing people with tiny blades.
I already agree with you that what is too dangerous to be let on a plane seems arbitrary to the lay person, but I suppose they judge the likelihood of certain kinds of threats being lethal or dangerous on a plane and go with their judgments on it, right or wrong. Someone is going to do that job, and the reason why is because people need to earn money to make a living, and the government is going to want to cover its own butt if something bad goes down. Further, the reason why we have such beefy security now is because whenever there's a crisis everyone panics and demands maximum security. This is the end result.
I'm not saying I agree with it. And since I don't know, and most people don't know what is or isn't threatening (look at how they feel about guys dressed as Imams. Lots of terrorists forget about disguises and go plan their attacks dressed as clerics....), someone makes that assessment for us and it makes some people feel safer, and that allows some of them to fly on planes, and that allows airlines to make money, and flights remain within an affordable range for common people, I guess.
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