Alright. I said I would post when I had time. So here it is. Also, this is not what I believe to generally be right as a rule. I am answering the question "Would you kill someone to defend your property." That said, I am not speaking legally either.
What I was saying earlier to Peter was only a tangential part of my full response. Many people have suggested that a human life is more valuable than any object or material property. My response will largely stand in opposition to that viewpoint, as it pertains to me.
There have been distinctions made between harm towards your person and harm towards your property, whereby lethal defense is noble in one case and not in the other. In my estimation these two are one in the same. I'll try my best to explain with two Scenarios.
Scenario 1. A man breaks into my house and I catch him. He's armed with a pistol and intends to shoot me. Now, regardless of what happens, I face personal damage by any definition. I may never be able to ride my bicycle, race cars, or shoot hoops ever again. In this scenario, I believe most of you will agree that I would be justified in defending myself. Fine.
Scenario 2. A man breaks into my house with the sole intention to steal my car. Like the first man, he will still be depriving me of something that is rightfully mine.
The common misconception is that it is something that can be replaced. Rest assured this is not the case. It's true that another car can be bought, but there is more that factors into a vehicle, or any other property than just spending money. The cash used to buy the first car didn't materialize from thin air. It was paid for for by the time I spent at a job that I've fought hard for. That time lost can never be repaid. There is no restitution in Justice for time lost, because the nature of Justice is reactive, not proactive. Even if justice through the proper authorities is served, I will not be compensated for that part of my life lost.
My analysis of Scenario 2 does not even weigh in the psychological damage caused by having your belongings stripped from you. When I was 15 I was on my way to a bus stop and I was cornered while walking through a parking garage by two Koreans and a black guy. They only hit me twice. But for days I felt violated, picturing their hands in my mind rifling through my pockets to strip me of $32, my school bag, and all my books. I had to walk home. They didn't even leave me enough for my bus fare. The punches hurt for hours, but having things taken away from me hurt for much longer.
I see no difference between defending myself and defending my valuables. Taking away my property is depriving me of a standard of living I have worked hard and justly to maintain. I will fight to the death if necessary to protect that standard, which I have invested so much time and effort into. The value of any man's life who wished to deprive me of my standard of living is zero in my eyes.