Of the many theoretical and conceptual debates currently ongoing in international relations, some of the most promising revolve around rethinking what the object of study is. That is, how are international (or global, or world) relations properly or most pragmatically conceived? The nation-state as the main unit of analysis has been displaced by decades of critical scholarship that emphasizes the contestable and constitutive elements of states, and the violence conducted by them across “inside/outside” border(s). These two books position themselves squarely within these critical traditions, yet their arguments should resonate with all IR scholars concerned about the serious challenges faced by a field whose charge is the study of a world that not only perpetually outpaces its analytical frameworks but also increasingly throws up challenges for humanity that exceed our current forms of political order.

With these broad intellectual contours staked out, the books would seem, upon first impression, to have little to do with each other. Jason Dittmer’s Diplomatic Material is an innovative study that substantially broadens how we think about the makings of foreign policy. Stefanie R. Fishel’s The Microbial State is a creative recasting of metaphors of the “body politic” upon which IR has long relied. Yet despite their contrasting empirical foci, both works share at least two sets of concerns. First, they both make compelling arguments for the value added of “more-than-human” frameworks as tools for IR. Such perspectives broaden our horizons to networks of materialities and objects upon which human agents act, yet which also act upon us. These are not only the traditional materialities of military force. Instead, such networks involve the everyday environments of buildings, architecture, microbes, and the planetary biosphere itself as phenomena in which humanity is inextricably embedded, which we affect but that also affect us in previously underexplored but profound ways. More-than-human frameworks, then, mean precisely that: shifting IR as a field focused largely on the study of human agency toward one sensitive to the multiply layered material, emotional, biological, and environmental contexts that shape us. In this regard, both authors adeptly employ the concept of assemblage as a key interpretive and explanatory resource. Second, both books aim to deploy these perspectives to self-consciously make an intervention into the world. Their innovative methodological stances conceive of “methods” not only as means of analyzing data but much more substantively as acts that bring into being spaces of experimentation. Both Fishel and Dittmer provoke IR scholars not only to think differently about their chosen cases (at which their respective analyses excel) but also to consider the strides the field might make if it were to shake loose some of its assumptions about the central place we give to humans within the much wider world we inhabit.

Diplomatic Material skillfully takes up these challenges by bringing new materialist approaches from cultural and political theory to the study of key episodes of British foreign policy from the eighteenth to the late twentieth century. Dittmer’s analytical route into these episodes is through what he calls geopolitical assemblages (p. 2), an approach that allows for the analysis of “material circulations—of media, of objects, of bodies and their practices—that produce elite political subjectivities” within the shifting understandings and components of what has become known as the “international community” (p. 3). Thinking about the international community as an assemblage enables an approach to foreign policy analysis that is in distinct contrast to macro-scaled and structural frameworks, and is useful in spotlighting and making sense of the crosscutting forces at work on foreign policy elites that stem from their unique positioning as hinges of multiple alliances, arrangements, national, and international cultural forces simultaneously (p. 4).

It is through this contrast with more standard theories that Dittmer elaborates the analytical potential of assemblages in terms of the micropolitical sites of everyday foreign policy practice. Assemblages can be understood as contingent configurations of heterogenous elements that are ever shifting and that have effects upon agents, but whose effects cannot be determined or predicted prior to their instantiation (pp. 9–10). These are configurations of human bodies and the material items and spaces with which they interact. A focus on assemblages as foreign policy analysis has the effect of shifting attention away from the state and toward the “diplomatic system itself as a type of body politic” (p. 11). This diplomatic system, and those within it, “enables the channeling of affects from beyond the state assemblage into the very heart of power” (p. 13). One of Dittmer’s main arguments, then, is that a more-than-human approach reveals a multidirectional flow of affects and ideas within diplomatic sites that can have the great effect of reshaping ideas of the “national interest.”

Dittmer’s cases nicely lay out what this approach brings in terms of a “counterhistory of British foreign-policy making” (p. 19). Chapter 1 offers a history of the British Foreign Office and how from the eighteenth century, the very real materiality of rapidly increasing reams of paper, resulting from the need to administer the growing empire, prompted actions and architectural debates over the building itself, which in turn shaped Foreign Office policy. Chapter 2 offers an account of how official protocols developed during and after World War II fostered embodied routines that enabled trust to replace suspicion between the UK and United States (p. 51). Chapter 3 examines how standardization of arms and procedures within NATO countries helped the organization to cohere over time, while Chapter 4 examines the making of contemporary European Common Foreign and Security Policy (CFSP) through the affective and temporal rhythms that must coincide between the UK and the European Union.

Fishel’s study takes as its starting point the long-standing use of “body politic” metaphors in thinking about international relations. One need only recall the frontispiece of Hobbes’s Leviathan (which Fishel does, p. 30) to see the centrality of such metaphors in IR, along with other commonplace tropes such as “organs of the United Nations, the family of nations, and heads of state” (p. 25). Yet Fishel’s argument extends much more broadly. Indeed, while deftly illustrating command of wide swaths of the field, she positions IR’s dilemma not only in terms of the need to deconstruct such metaphors. She further suggests that it is what such metaphors do that is the problem. For our standard metaphors for the “body politic” privilege human beings in a world that is very much more than just human beings, and positions them as masters over nature and everything nonhuman, all the while such nonhuman forces are showing signs of molding and changing human civilization in soon-to-be catastrophic ways. In this way, Fishel “challenges the reader to think of politics as immanent to the biospheric rather than the anthropic” (p. 2). This is a clear ethical intervention as well, as the author asks IR to shift its conversations from states and national power instead to “care for bodies, both human and non-human, in an environment that is unpredictable and often violent” (p. 4).

Fishel shares with Dittmer an interest in new materialist and assemblage approaches as tools that can help us to think differently about what we consider to be “international relations.” Fishel zooms in and out of micro- and macropolitical perspectives, from seeing the human body itself as an assemblage of organs, brain, and bacteria to humans as one part of planetary assemblages of the biosphere. She draws upon a range of literatures largely outside of IR, including immunology and science and technology studies, to offer an account of humans as sharing the biosphere with other forms of life that depend on us and upon whom we depend. Not only does this illustrate our place in the wider web of life, but it also demonstrates the error of scholarly approaches that center the human and assume its mastery over the rest of life.

It is from this picture of humans as part of other forms of life that Fishel builds her argument about metaphors. For her, “if we speak about the world differently, we will treat it differently. This means talking about bodies and worlds differently” (p. 39). Drawing from George Lakoff and Mark Johnson’s work on the power of metaphors, Fishel focuses on microbes and their intimate relationships with the human body, an overview of human and nonhuman lived reality. From this she develops two novel metaphors—the “lively vessel” (p. 61) and the “contaminated state” (p. 91)—to unsettle the still-dominant “state-as-person” metaphor in IR and to reengage it with a view toward the myriad of relations (from microbial to macroscale) that constitute bodies/states, for which a posthuman ethics is needed.

Both The Microbial State and Diplomatic Material amply succeed in retraining long-standing IR concerns onto terrain that more effectively engages with the many ways in which the nonhuman and human worlds inevitably intermesh. Part of the allure of assemblage theories in other fields (such as sociology and human geography) is their radical potential for rethinking traditional notions of causality, and how they might shake up the divide that has developed in IR between “causal” and “constitutive” approaches, an issue that neither Dittmer nor Fishel takes up. However, more importantly, Fishel’s and Dittmer’s respective studies should spark IR scholars to reconsider the ethical implications of putting human agency at the heart of our analyses when it is now clear that agential effects emerge along a spectrum of human and nonhuman phenomena.