Why are righties more likey to harm home intruders?

I am more of a "lefty", and I think I might advocate violence in defending my home or family. That being said, the level of harm I am willing to do to an intruder would have to be comparable to the level of the threat that person or persons posed. A teenager breaking into my car to get my Ipod doesn't deserve to be killed, but a group of men gang raping my wife would be killed. None of my property is worth my life, and in event of a property crime, I would opt to let the police handle it if possible, but I think anyone would react violently to a threat to their loved ones.