Just for the record - last year Idaho enacted a very strong stand your ground law. You have the right to defend your home AND your business AND your car with deadly force. You don't have to be in fear of your life and you don't have to retreat. You have the right to defend your property. If Antifa hits your home, your store, or your car, you have the right to shoot.
I do question how this would play out with militia. They don't own your stuff. How would the courts view their actions if things get lively?
The way the law works is that defenders of third parties stand in the shoes (legally speaking) of the parties they are defending. So if the owner would have had a lawful right to use lethal force, then so does the citizen coming to his defense.
Jurisdictions differ in this only with regard to the question of being right in evaluating the situation. Some jurisdictions require that the defender of a third party be correct in his assessment of the situation, while other jurisdictions only require that a reasonable person in his shoes would have perceived the situation the way he did, i.e., as a situation justifying his defensive actions, even if it turned out that he was mistaken about the nature of the situation. In other words, the mistake has to have been reasonable.
