Lets say someone tries to rob you and is unarmed, then you go ahead, shoot him in the face and kill him.
Murder or Self Defense?
If murder, where does it begin to be defense. When he has a knife? When he has already attacked you?
If self defense, I can see a lot of situations of pure murder where the shooter claims that they were being robbed.
Yeah I know, more stupid hypothetical scenarios...
Robbery: The nation's fastest growing career!
Duties: Giving the people their bread and circuses, extracting payment by force, validating legitimacy, etc.
Job Outlook: Ever increasing and shows no signs of stopping!
If someone is robbing you, they clearly intend to hurt you, and you have every right to destroy them in self preservation. No point wounding someone violent, only to have them kill you after you think you've done enough.
Periodically the tree of liberty must be watered with the blood of tyrants and patriots.
Thomas Jefferson
Unarmed robbers probably won't be stupid enough if you're holding a gun. You could argue that he was trying to get your gun to shoot you instead - still not a bright move on the part of the perp.
The mythic knife fight is just that...a myth. If the perp presents a knife, a gun is an approriate response - and don't hesistate because once the perp is on you, you're dead even if you manage to kill him. A blade in the gut or across an artery means you'll probably die before the perp you just shot, unless you shot him in the face or other critical spot. Liberals go on and on about gun control, but a knife in the hands of someone who can use it can be as devastating.
Shooting to wound isn't a self defense move. It suggests you had the opportunity to escape, and therefore you intended to harm someone. Using a weapon in self defense means that you believe your life or the lives of your family were in immediate danger.
If you have a way to escape the situation, then that's the best course of action. Professional criminals know it's much harder to handle a person who is attempting to escape than it is to handle an unskilled person who's trying to defend himself. In an Anarcho-capitalist or minarchist society, it's the violation of your property rights that you can pursue some form of compensation - you don't necessarily have to kill the perp, and in fact that could be viewed as disproportional punishment.