Comments about ‘A man comes onto a bus with a gun. Now what?’

Snake. You are wrong. Nothing in the Constitution gives you the right to know anything about that individual. Nor is feeling safe a constitutional right.
Saying, "I have the right!" Believing, "I have the right!" is great... it's cool. it's awesome. But it does not mean that constitutionally the right exists!
Free Speech, Press, Assembly, Keep & BEAR Arms, Protection from; quartering, search & seizure, cruel & unusual punishment, due process, trial by jury....
You DO NOT have a right to know. You DO NOT have a right to 'feel safe'.
Your country, constitution, citizenship, taxes...none of these provides for a RIGHT to know anything about me or any other individual. Nor does it provide you a RIGHT to clean air or a feeling of safety. If you want to feel safe..... provide for your own safety. Do what is necessary to protect yourself.