I have flown with some dominant but unstable people who considered themselves infallible and were unaware of their weaknesses and potential to be wrong. I would be deeply unhappy to think that some of them were now to carry firearms. Indeed, I would not, of choice, fly on their airline.
I can understand a lack of confidence in the ground security measures in place at airports world wide, not uniquely the USA. I feel that a more appropriate response is to ensure that those entrusted with ensuring our safety from a ground initiated attack do so in an intelligent and professional manner. Leaving those whose expertise is flying and managing an aircraft to concentrate on their job in an intelligent and profesional manner.