A central theme in the study of international relations is that anarchy requires states to set aside moral concerns to attain security, rendering IR an autonomous sphere devoid of ethical considerations. Evolutionary and moral psychology, however, suggest that morality emerged to promote human success under such conditions. It is not despite anarchy but because of anarchy that humans have an ethical sense. Our argument has three empirical implications. First, it is almost impossible to talk about threat and harm without invoking morality. Second, state leaders and the public will use moral judgments as a basis, indeed the most important factor, for assessing international threat, just as research shows they do at the interpersonal level. Third, foreign policy driven by a conception of international relations as an amoral sphere will be quite rare. Word embeddings applied to large political and nonpolitical corpora, a survey experiment in Russia, and an in-depth analysis of Hitler's foreign policy thought suggest that individuals both condemn aggressive behavior by others and screen for threats on the basis of morality. The findings erode notions of IR as an autonomous sphere and upset traditional materialist–ideational dichotomies.