The idea of self protection starts with your brain. First, you have to realize, no matter how safe you feel, there may be some a hole come along and ruin it. It can happen in your bedroom, your favorite fishing hole, getting out of your car. The simple fact is, there are persons that are out there that will do you harm with no personal vendetta against you. You may be a innocent bystander, or you may be a target because you have something that someone else wants.
A gun is a great responsibility, it is deadly force, you will have to use your brain to make a decision to end another life. A knife, pepper spray, squealing like a little girl may make a difference. But if an armed criminal wants to do me harm, I want equal force or superior force. I want to prevent someone else from doing me harm, end of story. It is that simple, cut and dry.