The just war tradition is the most dominant framework for analyzing the morality of war. Just war theory is being challenged by proponents of two philosophical views: realism, which considers moral questions about war to be irrelevant, and pacifism, which rejects the idea that war can ever be moral. Realism and pacifism offer a useful starting point for thinking about the ethics of war and peace. Feminists have been engaged with the just war tradition, mainly by exposing the gendered biases of just war attempts to restrain and regulate war and studying the role that war and its regulation plays in defining masculinity. In particular, feminists claim that the two rules of just war, jus ad bellum and jus in bello, discriminate against women. In regard to contemporary warfare, such as post-Cold War humanitarian interventions and the War on Terror, feminists have questioned the appropriateness of just war concepts to deal with the specific ethical challenges that these conflicts produce. Instead of abstract moral reasoning, which they critique as being linked to the masculine ideals of autonomy and rationality, many feminist argue for certain varieties of an ethics of care. Further research is needed to elaborate the basis of an ethical response to violence that builds on philosophical work on feminist ethics. Key areas for future investigation include asking hard questions about whom we may kill, and how certain people become killable in war while others remain protected.