I'm sure this topic will spark some good debate, so I figured it was worth posting! I almost always concealed-carry my Glock when I fly. Obviously I'd never draw or even brandish my weapon unless I legitimately thought my life or someone else's life was in danger, but I do worry about the odd whack-job who takes issue with me flying my scary drone around. I know, it sounds nuts, and it's insanely unlikely I'd ever need to use it, but I like to be prepared.
And in case you're worried Joe Schmoe is making the drone hobby look bad running around with his piece, I'm a former Marine who served as an armed security guard at US Embassies. I'm very well trained with weapons and the use of force. That said, I still believe the best weapon in most situations is your words.
So, do you arm yourself while you fly?