This conclusion pulls together the previous chapters. Arendt’s moral philosophy is, first and foremost, a moral psychology that turns on the concepts of thinking, judging, and common sense, and the catastrophic consequences of their absence. Its normative core lies in respect for human dignity, which she roots in the human conditions of plurality and natality. The chapter explains why Arendt’s early ambivalence about morality rests on mistakes. It then returns to four issues catalogued in Chapter 1: the problems of incongruity between person and act; the problem of principles and particulars; the problem of judgment; and the problem of moral realism. The chapter summarizes and expands on the solutions Arendt offers to these problems. It concludes by explaining the connections between Arendt’s moral thought and her ideas about international law. Holding perpetrators accountable for core crimes is one crucial way of acknowledging human dignity and of realizing the “idea of humanity.” Although Arendt is objectionably purist about the mission of international criminal justice, her contributions to its theory are impressive. They include a deep analysis of the crime of genocide, a critique of sovereign immunity, a recognition that states can be criminals, and an understanding of why some crimes are of international concern.