Ok, if I shouldn't _shoot_ the intruder, then...?

Yes, because in that moment when you wake up in the middle of the night hearing noises downstairs, and the only other person who should be in the house is lying beside you, all those things would go through your mind.

The point is, to make your house that much of a deterrent for all except the homicidal nutjob burglar - who tends to just kick your front door in while you are having your tea - rather than have to worry about what you will do if someone gets in.