Capt. Dan
That is why I live in the great state of Alaska where we have laws that make sense. Every situation is different and I would be willing to bet the charge won't stick unless he gets a liberal jury. I have asked lawyers and am trained in carrying a concealed firearm. If you feel you life is being threatend, especially in your own home you have the right to shoot that individual.
I don't know who your lawyer is but whoever gave you the advice that you can't bring a gun to a knife fight is entirely wrong. If that was the standard, picture a 120 lb woman being attacked by a 220 lb man, does she have the right to shoot him even though he has no gun?

BTW, What would you do if a guy was climbing through your window a 2:00am?