The health care needs of people in both developed and underdeveloped countries experiencing violent conflict are strikingly similar. Nurses are key for infectious disease detection and control, social support, and rehabilitation during terrorism and war in many countries. Nurses already provide much of the care in these situations because they are present on a day-to-day basis, have key clinical and organizational skills, and tend to enjoy a high level of popular trust. There is a great potential for the profession to do more with systems training, skill development, and participation in policy and research related to reducing the effects of conflict. This is applicable for both terrorist events in developed countries and for humanitarian crises in developing countries. However, nurses have frequently been invisible, serving without discipline-specific orientation. This is partly the result of unresolved ethical and political issues among nursing leaders regarding the image and role of nursing, humanist values, and relations between the profession and the government. Major nursing organizations frequently support national pro-war policies, whereas nursing leaders more often stress support for an international humanitarian orientation. These issues have been with organized nursing since its origins with Florence Nightingale. With better organization, autonomy, and recognition of nursing's unique contributions, nursing can achieve much more in situations of conflict to prevent harm and facilitate recovery among individuals, families, and their communities. Elements of an agenda for nursing research and development are detailed.