OK fair enough, but by using the word nutter, you gave the impression that you felt threatened, now you say it was only what he said. I certainly would not hit anyone on a plane just for what he said. Why do you think the flight attendants stand at the door watching everyone as they board the plane, they are weighing everyone up as they enter.
I was trained how to hit properly and use my fists, so I would not be damaging my hand.
Could you explain roughly what he said to you that had you worried? If he was such a nutter, why did you not have a word with one of the flight attendants?