Now that I think about it, maybe she attacked a Japanese soldier (Yanagida just happened to be the closest one) for a double purpose of causing an incident in the hopes it would get back to Tyuule and the prince) and also hoping she would herself get killed as a punishment for hurting these folks whom she obviously had started to like. She didn't try to kill Noriko anymore because Noriko's just a civilian and because that would actually be following Tyuule's orders to the letter.