In his new book, Rein Müllerson takes an eagle-eyed overview of current geopolitical games in world affairs and challenges the reader to reassess established tenets of prevailing patterns of thought.

The book is divided into four chapters with self-explanatory titles: (i) Geopolitics and International Law through the Prism of Ideology; (ii) Processes of Homogenisation and Heterogenisation in the World; (iii) The West versus Russia or vice versa?; and (iv) The Future of International Law. In a short final part (in lieu of a concluding chapter), Müllerson, recalling the Marxist spiral theory of history, warns against a Pax Technologica Americana which could result in ‘a slave-owing world at its highest possible level of development’Footnote ¹ spiralling towards a revolution with catastrophic consequences, given the modern state of military capabilities. However, the author’s final note is more optimistic – he believes in a democratic world order accepting of differences between societies and attentive to their free development.

Müllerson’s monograph does not make for light reading; it requires a certain level of understanding of modern politics and a willingness to keep an open mind to think outside the box. Indeed, in terms of methodology, it paves the way to a new vision in the science of international law and international relations.

Müllerson knows intimately the societies which he analyzes and is able to look at them both as a scientist studying his subject from the inside and as an external and impartial observer. Müllerson explains his method as the study of ‘international actors as molecules, which may have different sizes, agendas and functions, but to which the researcher does not have any emotional attachment or revulsion’.Footnote ² This approach allows the author to achieve the desired result – to create a model of an international system that explains objectively the processes taking place therein and to discover the vector of their development.

The three pillars shaping the world as it exists today, as well as the author’s methodology, are: geopolitics, ideology and international law. They allow for the creation of an inclusive and consistent theoretical approach which portrays contemporary developments in an objective manner – to the extent that human nature can achieve this.

For Müllerson, the main focus of attention in this three-pillared theory is geopolitics, which is both a building block of international relations and a tool which helps us to understand and predict patterns in the evolution of the latter. As he points out, geopolitics explain how the geographical factors that circumscribe a state serve to determine its actions. It should be noted that an approach based on geopolitics is far from being a recent invention; such an approach can be an efficient and precise instrument only in the hands of an eminently skilful researcher, of the calibre of a scholar such as Müllerson. While not excluding the relevance of other factors, geopolitical reasons, in the vast majority of situations – directly or indirectly – play a key part in the motivation behind the behaviour of actors on the international plane. In recent history, each arena and instance of conflict or international tension can be described and explained in terms of geopolitics. The former Yugoslavia, the Middle East, Libya, Syria and Ukraine – all these are contemporary examples of battlefields characterized by geopolitical interests, actions and counter-actions of states engaged in geopolitical rivalry on the world stage, predominately with the USA and its allies, on the one hand, and with Russia, on the other.

However, in order to create a comprehensive theory capable of modelling developments and patterns on a short- or even long-term basis, a geopolitical approach cannot be the only means of analysis and needs to be complemented by other approaches and theories. To that end, Müllerson embarks on an examination of the current international situation through the prism of ideology. He notes that this tool is indispensable because throughout history, ideology, be it secular or religious, has been omnipresent in international relations and, not infrequently, differences between ideologies have been the source of inter-state conflicts; moreover, as Müllerson observes, in the second decade of this century, ‘clashes between different ideologies’Footnote ³ threatening the stability of the whole world system have not diminished but rather intensified.

The third pillar on which the world rests, as per Müllerson’s methodology, is international law as a body of rules ensuring the orderly conduct of affairs between states. He observes that modern international law first appeared as a world system (initially, in the seventeenth century as a European phenomenon) whose development coincided ‘with the emergence of relatively equal centralised nation-states’.Footnote ⁴ Expanding on this notion, he argues that modern international law – in essence, the product of a horizontal interaction between states and a co-ordination, rather than a subordination, of their wills and interests – can exist and function efficiently only within a multipolar paradigm. International law and a monopolar world are mutually exclusive. According to the author, three factors must be present in order for international law to fulfil its role as global regulator – ‘multipolarity, balance-of-powers and concert of powers’.Footnote ⁵ However, Müllerson argues that the simple existence of these three factors is not, at the current juncture, sufficient to provide a solid foundation for international law in the twenty-first century. He explains that, to be effective, international law requires a subjective element, namely general recognition or even the opinio juris sive necessitatis of statesFootnote ⁶ that these three elements are indispensable.

Explaining the functions of international law which make it indispensable for international society, Müllerson judiciously distinguishes between invariable and variable elements in the structure of law which correlate with the respective elements in the structure of society as a whole. Thus, according to the author, the principles concerning the sovereign equality of states, pacta sunt servanda, the non-use of force and the non-interference in the internal affairs of states may, in general, be qualified as invariable or partially invariable – as ‘not every part of their content is so invariable’.Footnote ⁷ They are those load-bearing components which maintain the integrity of society and stop it from collapsing. The role of these overriding principles is so important for the very existence of humanity that in the foreseeable future ‘their violation, even if frequent, cannot abolish them without undermining, or even bringing down, the very foundations of existing international order’.Footnote ⁸

On this theoretical basis, Müllerson deals with the most salient issues of inter-state relations and developments of international law in the first two decades of the twenty-first century. In particular, Müllerson discusses the reactions of states to terrorism in light of the right to self-defence and the nature of terrorist acts carried out by non-state actors. He notes that states may respond to terrorist attacks ex post facto or take preventive measures in anticipation of such attacks. The first category of states’ actions can be characterized as ‘defensive reprisals’ and the second as ‘anticipatory self-defence’. In any event, in both cases states are presumed to be exercising their ‘right of self-defence’. This broadening in scope of the right to self-defence to include armed measures against terrorist attacks by non-state actors was prompted by the rise in international terrorism, with acts of terror being perpetrated by various entities, ranging from individuals to organizations. He notes that, when the Charter of the United Nations was adopted in 1945, it was understood that, under Article 51, the inherent right of individual or collective self-defence in the event of an armed attack against a member of the United Nations could be exercised when an armed attack came from another state. However, it is undeniable that the twenty-first century has witnessed a new type of armed attack where ‘some non-state actors had acquired the capabilities to use military force against states that in their scale and modus operandi amounted to armed attacks as per the terms of the UN Charter and customary international law’.Footnote ⁹

This phenomenon needs to be looked at from different angles. In this regard, Müllerson refers to the issue of the responsibility of states from whose territory non-state terrorist organizations operate. Thus, he enquires into ‘the behaviour of non-state actors and the right of victim states and their allies (or the world community as a whole) to take coercive measures against such states’.Footnote ¹⁰ It would seem that another line of enquiry should be added here: what are the legal modalities of responses – vis-à-vis non-state actors – to terrorist attacks? Müllerson’s answer is clear and straightforward: if a state fails ‘to take effective measures to prevent its territory from being used by non-state actors that attack third states’Footnote ¹¹ because it is unwilling to do so, that state is in breach of the prohibition to use military force and has to bear the consequences for its illegal behaviour. This inevitably means that (leaving aside consequences under the law of state responsibility) states affected by terrorist attacks, by virtue of their right to individual or collective self-defence, are entitled to use military force against the state harbouring the terrorists involved in the attacks. However, if ‘a state … is unable to prevent its territory from being used by non-state actors against a third state’,Footnote ¹² it would not be right to hold this state responsible for a lack of action. That said, this does not exclude military actions against these non-state actors on the territory of the unwilling host state.Footnote ¹³ In point of fact, this kind of military action can also be considered a form of self-defence against a non-state actor, rather than against a state. It would seem that this concept of self-defence, while being far from fully settled, could become a new trend both in state practice and in terms of the position espoused in various scholarly studies. However, Christine Gray, referring to post 9/11 precedents and modern literature, argues that it remains to be seen whether ‘a wide doctrine of self-defence’ has become a rule in international relations. In her view, ‘it is not clear that this practice is enough to establish a new wide right of self-defence in the absence of extensive state support for such a doctrine’. She points out that it is not easy ‘to explain how the right of self-defence against a non-state actor can justify military action against a host state’ and the right of the latter ‘to the territorial sovereignty and the prohibition of the use of force under Article 2(4)’.Footnote ¹⁴ In any event, it is obvious that, similarly to what has occurred in other situations, here we may be faced with a conflict of those norms which provide the foundation of the international legal order – thus making it necessary to find measures and establish appropriate rules in order to resolve such a conflict.

According to Müllerson, in addition to self-defence, there are other exceptions to the prohibition of the use of force in international relations. Using an a contrario argument, he advances a hypothesis that if a prohibition of the use of force makes ‘a prohibition of human rights violations’Footnote ¹⁵ unenforceable, then the first prohibition should be set aside. In particular, the use of military force is justified in order to prevent or put an end to serious violations on a massive scale of human rights, such as genocide, crimes against humanity and systemic violations of international humanitarian law. The author claims that in such situations the use of military force ‘may be morally justified as a necessary condition of these rights being rights’.Footnote ¹⁶ However, it would seem that moral justification alone for the use of force in these circumstances would not be sufficient. Of course, a humanitarian intervention will possess the necessary level of legality if it is authorized by the Security Council, but Müllerson goes further – for him, ‘in extreme circumstances … even without the Security Council’s authorisation’,Footnote ¹⁷ an intervention or the use of military force on humanitarian grounds is lawful and justified under customary international law as it has evolved to date.

Müllerson rightly notes that, despite a potential collision between principles and norms of international law and regardless of the underlying reasons, the main question to be addressed is how to resolve this conflict of norms. According to Müllerson, the criterion to take into account here is the ultimate goal of protecting human life. In practical terms, this means that the obligation to ensure respect for human rights will prevail over the prohibition to use military force in a situation where such force against a state is indispensable in order to prevent or stop massive and egregious violations of human rights by that state. The framework underpinning the use of force in this case should be, Müllerson contends, that ‘extreme human suffering, which one attempts to stop or prevent, has to be significantly and foreseeably higher than the human suffering that inevitably results from the use of force to end the suffering’.Footnote ¹⁸ The same criterion relating to the protection of human life would appear to apply in other scenarios, for example, when there is a clash between the principles of territorial integrity and self-determination. Each specific situation causing a conflict of norms should be carefully and dispassionately studied in order to avoid applying double standards.

It should be added that the apparent incompatibility between the fundamental principles of international law remains in certain circumstances a stumbling block in the practice of states and the subject of heated discussion among writersFootnote ¹⁹. Up to now, no common ground has been found on how to approach this incompatibility issue which, as our recent history of international relations has demonstrated, has serious implications for world stability. It seems that the test suggested by Müllerson would allow us to find a path which would bring together, or at least closer, the various schools of thought.

It is an indisputable fact that rules of international law are being violated in our contemporary world. This may lead to the conclusion that either international law does not exist or that it does not function well and is irrelevant in international relationsFootnote ²⁰. This prognosis is however unfounded. Let us turn our attention to domestic legal systems. Although statistically, episodes of violations of domestic legal rules are without doubt much more numerous, nobody has ever tried to claim, on this basis, that the law is not fulfilling its function in society. International law should be treated in the same manner, with a clear understanding of its role, limits and powers. Müllerson shrewdly states that the significance of international law is not undermined but:

There is a complementary element to Müllerson’s statement, namely that the violations most complained of concern a very limited number of rules of international law, although of primary importance for the maintenance of the world order, and cannot justify negativism in relation to international law. The manner of functioning of the majority of the rules of international law is sometimes not readily ascertainable and does not necessarily draw the attention of the public and the media. Nevertheless, these rules ensure the smooth interaction between states in various geographical areas and therefore provide a sound basis for the modern international system.

Müllerson undertakes a lucid and free-flowing theoretical examination of the empirical material, making use of his three-pillared approach, in order to foretell the foreseeable future. He visualizes the construction of a new international order as ‘a multipolar, balance-of-power and concert-of-powers world’ which ‘would accept differences not only within societies, as liberal orders do, but also between states’.Footnote ²² He predicts, however, that the United States, as the most economically powerful nation in the world, by virtue of geopolitical factors combined with economic geography and ideology, will for a considerable period of time have the means and potential to impose its values on the whole world. Future developments will to a large extent be determined by the interaction of these two factors – geopolitics and ideology. A word of caution should be added here. In several instances, throughout the book, in order to illustrate his thesis regarding the effectiveness of a balance-of-power system to maintain peace in the world, the author refers back to the experience of the nineteenth-century and argues that, after the Napoleonic Wars, the European concert of powers ‘guaranteed the longest peaceful period [1815–1914] the European continent had ever known’.Footnote ²³ Is it indeed so? Let us not forget that during that centenary of supposed harmony a number of wars shattered various parts of Europe – suffice to mention the Crimean War, the Austro-Prussian War and the Franco-Prussian War, which is a far from exhaustive list of the military conflicts in Europe in the nineteenth century. Even more significant is the fact that these were wars between or involving those states whose stated aim was to ensure the balance and concert of powers. Today, we live in a different world; nevertheless, the Marxist spiral theory of history is not perhaps without pertinence. If in the nineteenth century – a period during which Europe had indeed been the closest to a system of multipolarity, with a balance and concert of powers model of international relations – it was not possible to build a truly peaceful world, why would the application of this model in the twenty-first century allow us to avoid the mistakes of the past? As Müllerson himself appears to acknowledge, a geopolitical rivalry at any given moment would be liable to re-introduce conflictual elements in the international system.

The current geopolitical situation and contemporary processes in international relations may create the impression that we are witnessing an alarming evolution of the world. In response, analysts are seeking to shine a light on potential future developments.Footnote ²⁴ Rein Müllerson undoubtedly is at the forefront of these researchers and provides well-founded answers to numerous questions that we are raising about our contemporary international system, its development trends, the parameters within which it functions and the role of international law in the post-modern world. Müllerson’s new book is indispensable reading for those who want to espy the dawn of a new order and participate intellectually in its shaping.