Thanks guys. These are the kind of answers I was looking for. I know the TSA has a long list of policy regarding what is and is not a weapon and what's permitted, which I find really funny, because literally anything can become a weapon with the right motivation. I saw a youtube video where a guy made a functioning one-shot firearm out of things bought in the airport inside security. I believe he used reenforced cardboard tubing as a barrel, hair spray combustible, battery ignition, maybe a golf ball projectile (?). The thing made a very violent shot. It comes back around to the fact that no law will stop those who are determined to exact evil. I think I'll be looking for a stainless Sharpee at minimum. I didn't even know they made them.