Some background sociology. A) The crazy woman in question had (apparently) not physically attacked the old woman (just verbally) People probably were waiting to see if things went further, first. B) Anyone on that train physically interfering with this woman probably stood as good a chance of being arrested as the woman herself, and might have needlessly escalated the incident. (Any cop will tell you that the amount of force needed to restrain a disturbed person while simultaneously protecting oneself can be.....unfortunate. And thats by people with handcuffs available!) C) Several people in the train told the woman to stop, and eventually she was physically "warned" when she became increasingly agitated. Actually the people on the train acted with much more self-restraint against an obviously disturbed woman than many "others" apparently would have. Conclusion: Problem (roughly) dealt with, and no "going postal" was required. Afterward: Interestingly enough, many outraged citizens suggested reactions to this situation seem to be much more physically violent than the actual incident itself!