Structure and sin: the Niebuhrian roots of Waltz’s neorealist theory of international politics

Prominent IR scholar Kenneth Waltz has acknowledged Christian theologian Reinhold Niebuhr as a major influence. Yet Waltz’s neorealist theory of international politics claims to be strictly ‘third image’ with no room for ‘first image’ considerations, such as Niebuhr’s emphasis on the explanatory role of ‘sinful’ human nature. This article claims that the significance of Niebuhr’s Christian realism for Waltz’s neorealism has been profound, much more so than Waltz and IR scholars generally have recognized. Three arguments are developed. First, Waltz’s own early attempt to transcend Niebuhrian realism falls short. Second, Waltz’s anarchic balance-of-power theory is basically Niebuhrian. Third, Waltz’s assumptions about states as egoistic security-seekers can be properly comprehended from Niebuhr’s realist theology. As invoking Niebuhr leads to a deeper understanding of Waltz’s theory, Niebuhr may be considered the ‘father’ of modern realism, structural as well as classical.
Keywords: Kenneth Waltz, Reinhold Niebuhr, neorealism, Christian realism, IR