There is no point is quoting gun deaths per capita, as the "facts" you find differ depending where you look. My opinion is that you should be able to defend yourself within the limit of the law, and in the USA it is your legal right to own a gun, therefore it is your legal right to defend yourself if someone breaks into your home, whether you should or should not is nobodies business as it has been decided back in 1791. It is down to you in that situation what you have to do, yes it may be that you are judge, jury and executioner, but come on if someone has broken in your home, they have already broken the law and infringed upon your rights and to boot if they have a weapon and may use it, then who could possibly say that if they were in the same situation they wouldn't defend themselves to the letter of the law. 
       Hopefully I will never have to be this situation, but if I am then I will use reasonable force, I don't like guns I am afraid of them, and thankfully I live in a country -England- where coming into contact with someone with a firearm is extremely rare, but if that happened in my home, I would want a gun to defend myself.