Way back up the line of this thread someone suggested acquiring a Rottweiler. I live alone in a smallish apartment and have a fourteen-pound rat terrier who thinks he's a Rott--I think of him as a micro-mastiff. No, he could not take down an intruder, but he invariably lets me know when someone is at the door. Occasionally it's a raccoon or stray cat, but he lets me know. Any edge in awareness is useful. Gives me time to come awake, begin to assess what's going on, and arm myself as needed.

The legalities and philosophical implications of using deadly force have been hashed out exhaustively here. If it's a life-or-death situation, the intruder's or mine, I will do what I have to in order to see to it that it's not my life that's lost. I would hate to have to kill someone, but even at 75 I'm not ready to die if I can prevent it.

What follows, follows. That's what lawyers are for.