Self defense is a skill that everyone should learn. As far as the use of a firearm...I am a CWP holder, I practice, practice, practice with every one of my firearms. I firmly believe in gun control, and that is why I hit what I aim at (Tip of the hat to pistolpete). As far as, "would you simply aim for the ankle to incapacitate the person??" No. Center mass, and shoot until the threat is neutralized. Also IMO everyone should learn and practice "situational awareness". There are way to many nitwits wandering around in a mental daze with no clue what is going on around them.
I carry a firearm because a cop is too heavy. When seconds count, the police are only minutes away. Police do not prevent crime, they investigate after the fact. Better to be judged by twelve, then carried by six.