I do not argue with your right to defend yourself (I believe every one has that right), and you certainly do not need my permission to do so.
That being said, if you and I were in McDonalds, and some wackjob came in and grabbed me from behind and held me hostage, and you had your gun on you that day, I would hope you would be competent enough in your weapon skills to take that motherfucker down.
Thats all.