It is argued that, in contrast to traditional interpretations, Morgenthau's theory of international politics is primarily concerned with the normative, and that, in contrast to revisionist accounts, the moral theory he generates is rooted in the Judeo-Christian tradition of moral thought. Morgenthau adopts an Augustinian, rather than Hobbesian-Machiavellian, moral framework, reconciling cosmopolitan principles with a recalcitrant reality by representing their relationship as a dialectical tension. This leads him to develop a practical morality which emphasizes the continued application of cosmopolitan imperatives to action, mitigated by a consequentialist orientation which demands that they be applied cautiously and always adapted to circumstances. This generates a political morality which reconciles the imperatives of morality and national survival by asserting that, while the national interest must be protected, it must always be subjected to strict moral limitations. It is therefore concluded that his approach ultimately culminates in a traditional, Judeo-Christian, nonperfectionist ethic.