An important part of learning to fight is learning to overcome psychological barriers against harming others. Though there are some interesting exceptions, most human beings experience signi cant internal resistance to doing harm to other people. (Marshall 1947, Grossman 1995, Morton 2004, Jensen 2012) Whatever its moral properties, this reluctance to harm can compromise the ability to fight effectively. Hence one might think that combat training should help trainees overcome such barriers. -/- However, on one compelling theory of evil, what (...) makes an action evil, as opposed to merely wrong, is that it is made possible by the agent's use of learned or innate strategies to overcome the natural barriers to harming others. (Morton 2004: 34{68) If this is right, it poses a prima facie moral challenge to these aspects of fight-training. The challenge is a special case of a more general one, namely, how it could be morally permissible to make people better at harming others? That is a question that martial artists rarely take seriously. Indeed, it is commonly thought that becoming a martial artist, and teaching the martial arts, are morally supererogatory. This paper takes the special challenge seriously, and looks at what can be said in response. (shrink)