What about non-violence

A gun to my head. William told me that during his time in South Africa he was robbed at gunpoint. The thief pressed the gun to his head and stole his money and, I believe, his car as well. He also said that many Chinese were killed while he was there.
Standing on the train. I stand on the MRT and be very still. I get these images in my head of fighting criminals and fending off thieves, but I have never been so unfortunate or fortunate to find myself in that kind of situation. William told me that his life was threatened without compunction. What would I do in that situation?
Run or fight? Would I try to defend myself against this person or would I give in to his demands? I like to think that I could move fast enough to get the gun and shove it up the person’s ass and see how he feels, but I doubt I could be so callous and daredevilish.
What about war? Should China attack Taiwan? Should countries war over water, food, oil? What would that be like? What would I be like? Would I have the guts, the stomach to kill someone? Would killing even be necessary? Gandhi speaks of non-violence, but what would he have done if he came across a soldier or a man raping his wife? Would he stand there trying to reason with him while the he continuously penetrates his wife as she lies there screaming? I doubt it. He may jump on his back and try to throw him off, or, lacking the strength, he may just get a large stick or rock and bludgeon the man. Despite his advocacy of non-violence, he probably would not just stand by while his wife was getting raped. He too must have had violent outbreaks on occasion.