If someone kicks down your door and comes running in with a knife and demands 'GIVE ME YOUR MONEY!!!' I think it is pretty much a sure thing he isn't so "innocent". If you decide to smoke him right there instead of retreating to the closet in your 2nd bathroom there isn't a jury in Florida that would convict.
What if the dirtbag has a knife and is about to stick your son/daughter/father/mother. Show me someone that would retreat instead of plugging the badguy and I'll show you a spineless liberal.