When I was asked to review Simon Polinder’s Towards a New Christian Political Realism, I was immediately enthusiastic. The book addresses a salient problem: how theories of international relations might better explain and incorporate the role of religion in international relations. Religious beliefs, as well as their strategic instrumentalization, demonstrably shape political behavior across levels of analysis, and IR theory should be able to account for these effects where they are plausibly consequential. It is equally clear that resources for such theorizing can be found in the writings of classical realists, whose work continues to inform the realist and other traditions and offers conceptual material to which contemporary scholars might productively return.

The bulk of the book looks to the past of realist thought to lay the groundwork for ideas to develop a Christian-inspired political realism, which is articulated in the final chapter. It delivers a thorough re-reading of Morgenthau’s and Waltz’s thoughts on international politics from the refreshing point of view of a scholar deeply interested in the role of religion for and in the development of the discipline of International Relations.

The author’s background is in the Humanities, in International History and Political Philosophy; so coming at this book as a died-in-the-wool IR theorist with a Political Science background, I did not find myself in familiar discourse, and the writing style presented some challenges. Yet, beginning in chapter 6, I was drawn in by Polinder’s thorough and wide-ranging re-reading of Morgenthau and Waltz, which brings a fresh perspective to ongoing debates in the historiography of IR theory and, in the end, really does develop interesting ideas for what might be developed as a new school of thought that can grant a greater role to religion (not necessarily only Christianity) in the analysis of international politics.

The introduction to the book contains a very brief overview of the Amsterdam School of Philosophy, which plays a role again in the last chapter by inspiring the proposed new Christian political realism. Unfortunately, the reader does not learn enough about this school of thought—its tenets are not systematically presented, and it seems to play no role in the hermeneutic analysis of realist thought that constitutes the bulk of the book. Its “practice perspective” is only brought in in the book’s last few pages. I would need more convincing of this school and its potential application in IR.

The introductory chapter further introduces us to a group of scholars the author refers to as “religionists.” They will become the foil for the author’s interpretations of Morgenthau and Waltz, as, basically, this book makes the case that realism can more easily be made amenable to consideration of religion than the “religionists” claim. Unfortunately, the tenets of the “religionists” are presented only fleetingly here; the reader has to piece their supposed views together from chapters 7 and 9, which juxtapose the author’s interpretations of Morgenthau and Waltz, respectively, to theirs, and from a table in the final chapter. Ultimately, I come away from the book not knowing whether the so-called religionists really exist as a coherent school of thought, nor whether, if they do, their views on IR in general and realism more specifically are worth interrogating. I could have done without them as a foil, as the interpretations of Morgenthau and Waltz Polinder constructs in chapters 6 and 8, respectively, are sufficiently interesting in their own right.

Chapters 2 and 3 essentially remind us that religion matters. Chapter 4 expands a little on “religionist” views on the realist tradition, while chapter 5 adds the author’s own ideas to this discussion. There is a valiant attempt here at a concise history of ideas to explain how realism came to deal with religion the way it has. Unsurprisingly, there is also plenty of room for disagreement with this history of ideas. Three notions struck me as especially productive: (1) the discussion of the reduction of religion in realism to its institutional, individual, and irrational aspects (pp. 55–57); (2) the suggestion, to be elaborated later, that Niebuhr’s and Morgenthau’s secularism was “theologically prompted” (p. 58); and (3) the insight that it is perfectly possible to be both a religious believer and a scientific positivist (p. 58).

Chapters 6 and 8 provide thorough and deep analyses of the thought of Morgenthau and Waltz, which are wide-ranging and not focused only on their treatment of religion or (implicit) theological views. Here, Polinder is able to provide a new and different take on old acquaintances. The discussion on Morgenthau explains why, in spite of being strongly drawn to Niebuhr’s views, Morgenthau moved classical realism further from religion. The discussion of Waltz contributes a focus on theological reasons for why religion is “de facto absent” (p. 135) in his theory. The discussion is especially interesting where it connects with the insightful work of Nicholas Guilhot and Carl Schmitt (pp. 85–88, 146, 164) to develop the notion of classical realism’s “theologically prompted” secularism as an anti-eschatological stance that embraces the autonomy of politics and the primacy of the state for the sake of katechon—a delay to the resolution of the fight of good against evil and thereby the end of the world as we know it.

The contours of the Christian political realism presented in the last chapter draw on tenets of the Amsterdam School of Philosophy and what the author calls the “New Practice Approach” to conceptualize international politics as a practice and raise the question of the telos (calling or moral purpose) of that practice. Two interesting suggestions are made here: One is the distinction between the rules of the game (constitutive rules) and the “regulative side of the practice” of international politics (p. 199). In essence, while religion might, as held by realists, not figure in the constitutive rules of the game of international politics, the worldviews of its practitioners, whether religious, secular, or quasi-religious, do play a role in the “unfolding of the practice” (p. 197). This is not an unfamiliar idea, but it is here expressed in a novel manner. Second, Polinder draws on Menno Kamminga to argue for “higher prudence as the supreme virtue in international politics” (p. 201). Here, alas, an opportunity is missed to tie the argument back to the tragic pragmatist position encapsulated by the state as international katechon. Higher prudence could, after all, be conceptualized as the acceptance of this role.

To conclude, Morgenthau and Waltz are, of course, not really “sufficiently representative of political realism” (p. 177) to base on a reading of their work general conclusions about how realism does, can, or should deal with religion. The alternative approach combining realism and attention to religion which the book works toward awaits elaboration in future publications. But this book offers interesting groundwork for such an alternative approach, and it is a thought-provoking read, especially in a time like this, when key world leaders seem eager to reject the task of katechon in favor of hastening the Second Coming.