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The Complexity of Bilateral Relations


This article showcases some of the ideas from Bilaterale Beziehungen als komplexe Systeme, published in German by Springer VS in January 2021.

Bilateral relations, past and present, have always enjoyed the attention of IR scholars and practitioners dealing with questions about war and peace, conflict and cooperation, concepts of world order, regional integration processes, international institutions or the foreign policy of individual states. Yet, in the course of my research projects on various bilateral relationships, German-French (Ludwig und Mahrla, 2014), German-Namibian (Ludwig und Rothauge, 2019) and most importantly British-German relations (Ludwig, 2011; 2020) it quickly struck me how little understanding of the driving forces, processes and effects of bilateral dynamics we nevertheless still have in IR. I argue, this sobering state of affairs is not only due to the surprising neglect of bilateral relations in IR theory but also related to the more general fact that most IR scholars and (to a lesser extent) practitioners have so far neither embraced complexity (Boulton, Allen and Bowman, 2015) nor taken its challenges and consequences in global relations seriously enough – an issue first raised in IR some thirty years ago by eminent scholars like John Lewis Gaddis (1992-3), James N. Rosenau (1990) or Jack Snyder and Robert Jervis (1993).

In this sense, this article invites the reader to rethink our previous approach to the study of bilateral relations in IR. Following some remarks on the current state of the field, especially concerning the influence of the relational turn in IR theory, I then shortly sketch my understanding of complexity and the opportunity of renewing bilateral relations research that comes along with it. Not least, these reflections aim to foster IR’s awareness of the inherent complexity of its subject-matter and the embeddedness of human global relations within global life as a whole.

Bilateral Relations Research in IR

The political and non-political cross-border relations of two social actors – still most commonly sovereign states – within the global system are the genuine matter of scientific interest in bilateral relations research. Although these have been recognised to be somehow important elements of the ‘international’, or – in more up to date terms – of the ‘global’ more widely, the field has long suffered from a theoretical and methodological shadowy existence due to its Janus-faced locatedness in the ‘nexus’ between the conventional analytical perspectives of IR (Harnisch, Brummer and Oppermann 2015), namely the so-called system level (with its focus on the international system) and that of the state (with its focus on foreign policy). On the one hand, this has contributed to a preference for historical-descriptive rather than theory-based studies, which is still evident today, but has been highly unusual in IR from the 1960s on. On the other hand, bilateral relations research persisted in a double self-limitation by adopting the ‘black boxing’ habit of mainstream IR theories (neo-realism, liberalism, Marxism and later conventional constructivism). It has thus simply mimicked the exclusion of different relevant factors, perhaps most importantly the individual, as well as the state-centred substantialism of the mainstream, unnecessarily narrowing its subject to inter-state dyads. Questions of dynamics, change and their driving forces hence remained just as marginalised as in conventional theoretical discussions of IR.

Accordingly, first attempts to renew bilateral relations research, for example, the Munich School of Neorealism (Kindermann, 1986), favoured a more holistic and contextualist multi-level approach to the analysis of bilateral relationships. However, it was only the constructivist and above all the relational turn in IR theory (Jackson and Nexon, 1999) at the end of the 1990s that, in my reading, meant a kind of quantum leap for the field: Now IR became more aware of the very subject of bilateral relations research – relations among actors – and slowly began to shift its ontological focus from substances to relations. This opened up the perspective of a new, truly relational bilateral relations research, centred on the dynamic-relational transaction processes among deeply social actors, always embedded in their global environment. In other words, the discipline has slowly started to recognise that:

It is relations that are not only at the heart of explaining and understanding the gimbal of global life, but also central to its observation and encounter. At the same time, relations are neither asserted nor imagined as pre-defined totalities. The epistemic verso of a relational IR is about the cultivation of attentiveness to the self-organizing, shifting, and historically and geographically contingent realities of mobile and relational global life. (Kavalski, 2018: 100)

Such a relational perspective on global relations has so far been received reluctantly – if not outright sceptically – among most IR scholars, though, which is not entirely surprising given the unbroken predominance of conventional, substantialist IR theories. An early and telling example of how an explicitly dynamic-relational approach to global life and bilateral relations might renew our understanding of both was Harold Saunders’ 2005 monograph Politics Is about Relationship. In it, he brings together his many years of practical experience as a US diplomat with relational and complexity thinking, whereby bilateral relations research came into contact with elements of both for the first time – if I see it correctly. For him, relationships are the ‘space between’. For their scientific analysis ‘[…] it is not enough to stop with a description of each party to a relationship and why each party acts as it does. It is not even enough to stop with a description how and why each party reacts to the other. We must go further to focus on the process of interaction between them […].’ (Saunders, 2005: 61)

At the same time, further theoretical reflections on relationality in IR (Jackson and Nexon, 2013; 2019; Kavalski, 2018; Nordin et al., 2019) show that, at least from the point of view of the study of bilateral relations, most dynamic-relational research still focuses too strongly on the question of identity formation. The unchanged reflex to marginalise both context and the individual has aggravated this deficit: ‘Indeed, a major wager of social-relational theories is that relational forms – networks, discursive configurations and so forth – should be abstracted from their cultural content and thick context for the purpose of causal inference. These theories downplay subjective motivations in favour of what we often call “structural” forces.’ (Jackson and Nexon, 2013: 559) The possibilities of understanding the dynamics of bilateral transaction processes thus remain limited even in a relational perspective understood in this way. Harold Saunders attempted to remedy both limitations using an analytical apparatus which, in addition to the identity of the actors, also includes their interests, power structures, perceptions and stereotypes as well as the processes and patterns of their transactions processes:

Each of these elements is itself complex; it is formed in continuous interaction with other persons or groups. These interactions shape and reshape the mix within each of the elements of relationship and the overall combination of the elements themselves. The changing mixes and combinations reveal how and perhaps why overall relationships improve or sour. Given the complexity of these changes within a continuously evolving process, it seems unlikely that they will be susceptible to measurement or prediction; but they are susceptible to thoughtful analysis and interpretation as a basis for action. (Saunders, 2005: 64-5)

These considerations point the field in a direction that increasingly understands bilateral relations as both dynamic-relational and complex social processes. Following these, introducing complexity more comprehensively is hence the next, and in my opinion consistent, step towards renewing bilateral relations research in IR.

Complexifying Bilateral Relations Research

So what is the core of complexity as I understand it? In contrast to previous systems theory approaches, it revolves around complex systems, their context-bound and contingent processes of self-organisation, their permanent change and the massive uncertainties involved, given the multitude of actors and influencing factors in continuous exchange both within the system and its environment. Complexity research is, as the British sociologist Sylvia Walby aptly summarised, ‘a loose collection of work that addresses fundamental questions on the nature of systems and their changes’ (2007: 449). It is not a closed body of theory, but rather a growing scientific approach. Its adoption and spread beyond the natural sciences has led to different readings and forms of complexity research in (Western) humanities and social sciences, which are reminiscent of the fault lines of the social science methodological dispute and the never-ending Second Great Debate in IR theory: a ‘US style of social complexity which tends to see methods developed largely in physics and applied mathematics as automatically transferable to the social world and a European tradition which has a much clearer relationship with philosophical arguments.’ (Byrne and Callaghan, 2014: 9)

Therefore, while the importance of complexity’s basic concepts – open systems, emergence, self-organisation, non-linearity and historicity – may be largely undisputed among complexity scientists, their ontological scope and thus the epistemological as well as methodological consequences of a complex world are not. Accordingly, it is essential to spell out one’s own position: In clear contrast to IR’s mainstream metaphorical or at best limited understanding of complexity, marked by its conventional positivist bias (e.g. Axelrod, 1997; Clemens, 2013; Harrison, 2006), I side with a more ‘general’ perspective, championed among others by the US philosopher Nicholas Rescher (1998) or the French philosopher and sociologist Edgar Morin (2007; 2008). Both explicitly criticise what Morin calls a ‘restricted’ notion of complexity:

Restricted complexity made it possible advances in formalization, in the possibilities of modeling, which themselves favor interdisciplinary potentialities. But one still remains within the epistemology of classical science. When one searches for the “laws of complexity”, one still attaches complexity as a kind of wagon behind the truth locomotive, that produces laws. A hybrid was formed between the principles of traditional science and the advances towards its hereafter. (Morin, 2007: 6)

A more philosophical take carries complexity’s paradigmatic revolution one step further indeed by explicitly calling for modesty with regard to the possibilities of measuring, explaining, predicting and thus controlling the world, and at the same time pointing to the double contextuality of all (scientific) observation of it.

In complexity thinking, neither the physical nor the social world is mechanical – regularities are not the basis for knowledge; there is no object/subject differentiation; the complex world is “unknowable” in the sense that prediction will always be undermined by uncertainty. In short, a complex approach to the social world will require a profound epistemological rethinking, or perhaps “unthinking”. (Cudworth and Hobden, 2012: 165)

With this science philosophical background, I conceive bilateral relationships as complex social systems. Such bilateral systems, like all social systems, are thought models or constructs that serve as concrete objects of analysis for an observer in a particular context (Cudworth and Hobden, 2013: 433). In contrast to previous conceptions in the field, bilateral relations are no longer understood as interactions between (reified) states, but – following a dynamic-relational ontology – as the continuous processes of transaction among the parts of a complex social system. Each of these comprises subsystems, from the two collective actors (still at the centre of scientific interest of the field) right down to the individuals. Besides, bilateral systems overlap with and are embedded in a multiplicity of other social as well as natural systems. Since every complex system arises from the relations of its parts, a bilateral one ultimately originates in the continuous transactions of the individuals – who are the essential basic unit of all social systems and complex systems themselves at the same time. They create, in the words of Harold Saunders, ‘[…] a shared context in which they interact – a world of their own. They create it together – often without talking about it; neither could create it alone; one cannot see it; but it is valued in its own right, and it shapes action.’ (Saunders, 2005: 62)

Accordingly, the subject-matter of a complexified field of bilateral relations research are the manifold transaction processes in a complex bilateral system that is in a state of permanent change as a result of these and regularly influenced by its environment – both social and natural. Unexpected developments, coincidences and (perhaps most importantly) the characteristics of individual actors (personality, memories, emotions, spontaneity etc.) add to the contingency of these processes in a specific and evolving historical context, thus making these dynamics ultimately uncertain and unpredictable. The search for timeless regularities or even laws, short a deductive-nomological approach that has long characterised IR research becomes untenable against this backdrop – just like the still common analytical practice of distinguishing between dependent and independent variables of supposedly causal chains or levels of analysis that can be clearly separated from one another.

In contrast to conventional theory-based approaches in bilateral relations research, a method for the analysis of complex bilateral systems has to take into account these permanent dynamics as well as the continuous processes of change, contingency and context, the influence of unexpected events, of chance and individuality. Short, I explicitly concur with John Lewis Gaddis (1992-3; 1996) and others that we need historical methods to analyse the development of complex systems over time in IR:

The point of having a model in science or a metaphor in history, is much the same: it is a way of coping with complexity. In this respect scientists and historians, as well as novelists, poets, psychologists, sociologists, economists, and even political scientists, are in the same methodological boat: we all resort to models […] not just for convenience, but because it is the only way we can understand reality ourselves, or try to communicate it to others. The historical narrative has exactly identical purposes to those of scientist’s models; indeed, because it need not depend upon reductionism, because it does incorporate the passage of time, and because it accommodates and even relishes particularity, it may be – if thought of in this way – the most sophisticated model of all. (Gaddis, 1996: 42-3)

In this respect, narratives are the ‘natural’ method of complexity research, when a complex system, the observer, strives to interpret and understand the complex environment with which he or she is inextricably interwoven. Therefore, following Geoffrey Robert’s narrative turn (2006), I propose the method of a complex historical narrative as a tool for the complexified analysis of bilateral relations. In a nutshell, a complex narrative is a meaningful reconstruction of how a complex (bilateral) system evolved over a certain period of time, which dynamics or processes of change brought it there and which concrete events, individuals and influences contributed to this and in what form from my point of view as a contemporary observer of these past developments.

Complex Bilateral Relations Research, IR and Global Life

The introduction of complexity thinking helps to tackle the long-existing deficits of bilateral relations research in IR and finally renders the previous double self-limitation of the field obsolete: A holistic perspective that takes into account the influences on the manifold dynamic processes of a bilateral system, right down to the factors of chance and individuality, eliminates the problem of ‘black boxing’. Since, from a complexity point of view, we are always dealing with interwoven social systems within the global system, the previous latent state-centrism of the field can be overcome: Dyads are complex social systems intersecting with and embedded in other complex social systems and ultimately global life as a whole. Hence, they may consist of different kinds of complex subsystems, such as (sub-)states, international organisations, transnational corporations, Global Cities, but in the end they always arise from their respective ‘individuals, each with different histories, capabilities and goals’ (Rosenau, 1996: 309) and their continuous transactions.

Thereby, I argue that the renewal of bilateral relations research for a world of massive uncertainty and permanent change is theoretically as well as methodologically possible and well-founded in my more comprehensive understanding of complexity following Edgar Morin and others. At the same time, the complexification of bilateral relations research indeed helps to (re)connect this field to the experiences of practitioners of global relations. This enables theory-driven research on bilateral transactions, their driving forces and dynamics in a complex world which is in a mutually enriching and critical dialogue with practice. For although complexity thinking can offer no easy answers, no simple solutions to the current challenges of our world, ‘it does indicate why the challenges we face are so difficult, and why the outcome of our acts can be so different from our intentions. Acknowledging this complexity would be a first step towards more effective action. Awareness of our embedded and contingent existence should make us more thoughtful about what we seek to achieve.’ (Cudworth and Hobden, 2011: 188)

Nevertheless, the reception of complexity in IR, especially the comprehensive perspective I advocate, has so far proven a conspicuously reticent and slow undertaking compared to other disciplines. Since the 1990s, there have been attempts to change this dire picture and especially in the more recent past, there have been several noticeable developments in IR theory pointing to an increased sensitivity to different aspects of complexity’s challenge for the analysis of global relations and IR – think only of Alexander Wendt’s Quantum Mind and Social Science (2015), Emanuel Adler’s World Ordering (2019) or Milja Kurki’s International Relations in a Relational Universe (2020). I am convinced that further impulses in this direction are much needed for IR to finally embrace complexity fully. In my opinion, only a discipline that is not only aware of the complexity of its subject-matter but also takes this condition seriously in its analyses will be able to contribute to the transdisciplinary efforts of providing scientific support to (global) society in dealing with the dynamics and challenges of global life.


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