1. ‘International Law as a Legal Order’: The MPIL’s Research Agenda
Viktor Bruns was not only the Institute’s founding director but also launched the Institute’s journal Zeitschrift für ausländisches öffentliches Recht und Völkerrecht (ZaöRV, English title: Heidelberg Journal of International Law, HJIL) in 1929, five years after the Institute took up its work. The first ever contribution was Viktor Bruns’ article entitled ‘International Law as a Legal Order’ (‘Völkerrecht als Rechtsordnung’). It was originally intended as the first of a series,1 but ultimately only one follow-up article was ever published.2
On the occasion of the Institute’s 50th anniversary, director Hermann Mosler once again dedicated an essay to ‘International Law as a Legal Order’ which was published in the ZaöRV in 1976. As their titles suggests, both contributions explore the extent to which international law is not merely ‘law’, but rather constitutes a ‘legal order’. Given the adherence of the Max Planck Society to the Harnack-principle, which aligns entire institutes with the visions of their directors, these articles can be seen as research programmes not only of the directors themselves, but of the MPIL as a whole. According to Mosler, when he wrote his article, it could ‘not be overlooked, that both points in time—the mid-1920s and the mid-1970s—offered favourable starting points for stock-taking and comparison. Between these poles lie the soon-to-be disappointed hopes for a strong international order […]’.3 The same can be said of the mid-2020s: Behind us lie the dashed hopes for a ‘New World Order’ proclaimed after the fall of the Berlin Wall in 1989.4
The Institute’s centenary is a good occasion to revisit the anniversary contributions by directors Bruns and Mosler. Parts 2 and 3 re-examine their articles, while part 4 analyses their similarities and differences. In part 5, I assess the lasting significance of both commemorative contributions. In part 6, I will present a renewed programme of conceptualising international law as a legal order, and will argue that this approach helps to understand deeply and to articulate a critique of international law that is needed in our current period of global re-ordering.
2. Bruns 1929
The historical context of Bruns’ contributions in 1929 and 1933 was marked by Germany’s defeat in the first world war and the Treaty of Versailles—perceived as unjust by many Germans—and the flourishing of international and transnational arbitration, which produced extensive case law to address the war’s consequences, particularly in determining compensation claims against the German state. These arbitral courts made the international law ‘material’ and ‘tangible’, according to Bruns.5 Yet, ‘today’s systems’ (by which Bruns meant scholarly systems) were insufficient to ‘capture this legal material’ and weave it into a fabric of law. Accordingly, Bruns tried to ‘fulfil the most important task of scholarship, which is to be ahead of the courts’ work and reveal to them [to the courts] the law’s systemic interconnections in a complete legal order’.6 Bruns’ scholarly interest was thus primarily practice-oriented. This is underlined by the many examples he took from treaties and court rulings, especially in the second article of 1933.
Bruns opened his first article with his central thesis: ‘International law is a legal order for the community of nations, a system of legal rules that are interconnected to form an order [Ordnungszusammenhang].’7 A legal order is characterised by its systematic structure. It is not an ‘unstructured compilation of rules and institutions unrelated to each other’.8
Moreover, and importantly, it is an ‘order in a twofold sense’: it (supposedly) creates order in social reality precisely through its own (internal) order.9 Put differently, Bruns argued that the existence of this inner structure is indispensable for enabling the law—particularly international law—to fulfil its task of ‘ordering’ the world. Bruns saw the ‘imperative of peace’ as ‘the essence of the legal order’.10 In order to bring about and guarantee peace, dispute resolution through (arbitral) courts was central—without it there could be neither order nor law at all.11
Because international law has this quality of a legal order, Bruns deduced that it positively assigns competences to states and that the states’ ‘right to personality and freedom’ must be ‘generally limited’. That right is intrinsically bounded because it needs to respect the rights of ‘the other members of the community which are equal in rank’. Otherwise ‘legal order would not be conceivable’.12 Bruns concluded that states could not (as a matter of legal logic) enjoy a general freedom of action, and drew this conclusion from his concept of legal order.13 Overall, Bruns’ goal was no less than ‘to find a system and method for international law’.14
3. Mosler 1976
In 1976, decolonisation was in full swing, with many new states of the Global South joining the United Nations as new members. This followed the founding of the European Coal and Steel Community (ECSC) in 1951—for which Mosler had advised the German delegation—and later the European Economic Community (EEC) in 1957. The Eastern and Western blocks had consolidated themselves, and the Cold War had begun. In this climate, two separate UN covenants on human rights had been drafted and signed in 1966 and were set to enter into force in 1977. The Helsinki Final Act of 1975 included a so-called human rights ‘basket’ addressing humanitarian concerns. Throughout the 1970s, the UN General Assembly adopted important resolutions that function as quasi-codifications of international law, ranging from the Friendly Relations Declaration (1970) to the Definition of Aggression (1974). These events are mirrored in Mosler’s characterisation of international law as a legal order. He identified and analysed the ‘four defining element[s]’ ‘of the international legal order’15 or the ‘modern international community’16: the first characteristic was the ‘explosion in the number of UN members’.17 The ‘second significant feature’ was ‘the organisational element’18—contrasting with the ‘unorganised international law’19 of the past. Under this heading, Mosler mentioned the increasing relevance of international organisations and provided numerous examples from the practice of the United Nations and the European Community. International organisations, according to Mosler, serve the purpose of ‘creating states through convention’ (by treaty).20 Through accession to these organisations, through the admission decisions of the organisations, new territories ‘with uncertain viability’21 were ‘promoted’22 to statehood. These new states of the Global South differed in ‘sociological’ terms from the old states of the Global North. Only the former had been ‘necessary members of the international law community’: ‘One could call them [the new states] conventional, but not sociological, or original, or spontaneous, states’.23 In other words, the new states were treaty-made but not organically grown. Their emergence and their admission to the international organisations ‘changed the character of international society’.24 Thirdly, Mosler noted the ‘revival of old differences between great powers and other states’.25 With that, he alluded to the privileged position of the P5 in the United Nations Security Council. The fourth characteristic was the ‘status of international legal relevance’ gained by human individuals ‘even vis-à-vis their own home state’s public authority’.26 Mosler held that ‘the core’ of ‘the legal status of the human person’ was guaranteed as ‘part of the ordre public of the international legal order’, and all the more so, the closer the protected status was ‘connected to human dignity’.27 (Here Mosler probably had the most fundamental human rights in mind).
Mosler’s approach to international law was practice-oriented, which first of all means doctrinal. For example, he explicitly rejected any ‘sociological foundation’ of law.28 ‘Pursuing a practice-oriented approach’ was, as Felix Lange has made clear, ‘a conscious, political programme’.29 Looking back, Mosler wrote: ‘because our discipline deals with certain political issues and because it is used and abused for political ends, one not only had to perform but also had to overcome distrust and rejection’.30 What Mosler had in mind was primarily the abuse of international law by National Socialist theories. Maybe he perceived any theory of international law to be prone to abuse. His predominantly doctrinal and therefore supposedly ‘apolitical’ approach was meant to safeguard against such abuse. With his approach, Mosler intended to reintroduce Germany into the international legal community. His strategy was successful: the Federal Republic of Germany was admitted to the United Nations (at the same time as the German Democratic Republic). Germany received this stamp of approval as a ‘peace-loving state’ (Art. 4 (1) UN Charter) in 1973, shortly prior to the 50-year anniversary of the Institute and 24 years after the foundation of the Federal Republic and the re-foundation of our Institute under the name of Max Planck.
4. Continuities from Bruns to Mosler
The political context, the state of development of international law, and the methods of international legal scholarship in 1976 were different from those of 1929. However, those differences should not be overstated, given the numerous lines of continuity. The institutional design of the United Nations was modelled on the League of Nations.31 The prohibition of the use of force, while placed on a new legal foundation in 1945, had already been conceptualised as early as the1920s, with the Briand-Kellogg Pact of 1928 as a milestone.32 Economic, social, and labour issues had already been concerns of international law, especially of the League of Nations and the International Labour Organization (ILO), in Bruns’ days. They remained salient in Mosler’s era.
The truly novel issues of the 1970s were decolonisation and the protection of the natural environment. The latter theme reached international law with the Stockholm declaration of the United Nations General Assembly in 1972.33 Mosler, however, did not mention this topic with a single word.
At first glance, Bruns’ vision of a strictly inter-state legal order34 and Mosler’s conception of a legal order which also encompasses international organisations and individuals seem to stand in stark contrast. However, Mosler still classified the new actors as second-class persons of international law. International organisations were, he argued merely ‘homunculi of states’35—created, sustained and potentially dissolvable by states. The organisations did not possess an ‘independent existence in themselves’ and were ‘not prior givens to the legal order’,36 they were not ‘primary or original or necessary legal persons’ like the (European) states.37 Similarly, the novel and legally significant position of the individual human being did ‘not affect the specific structure of the international legal order’.38 This order remained ‘fundamentally a legal order based on states’.39
Mosler appreciated Bruns’ conceptualisation of a coherent system of international law as a ‘legal order complete in itself’40 and adopted this view. For Bruns, ‘gaplessness’ or ‘closure’ meant that the rules and principles of international law were ‘complete’ and thereby both constituted and placed legal bounds on states’ freedom of action.41 Mosler embraced this idea of completeness.42 Like Bruns,43 he theorised that it is international law which defines the states’ powers and their limits.44 Both directors thereby rejected the Lotus principle of the Permanent Court of International Justice (PCIJ), which presumed a general freedom of action for states unless prohibited by international law.45
Both directors also shared a practice-oriented research agenda, best served by a doctrinal approach. Competing or complementary approaches to international law scholarship were either ignored by the directors or outrightly rejected. Both directors opposed a Kelsenian version of legal positivism, though Bruns did not offer any alternative theory of law.46 Bruns’ thinking was based on legal logic and was self-referential, with his arguments entirely dependent on their own legal premises. He dismissed several lines of reasoning as legally ‘unthinkable’ or inconceivable in legal terms, while his own thoughts were supposedly ‘a priori’ or ‘in accordance with the ‘essence’ (Wesen) of international law, or of order and the like, and thus correct.
In contrast, Mosler, explicitly grounded international law in natural law.47 He searched for the ‘basis of validity [Geltungsgrund]’ of international law48 and identified ‘constitutional elements of the international law community’.49
Despite their differences, both directors saw international law primarily as an instrument. It was considered a tool (or a weapon) to be used to advance German interests on the international political stage. The research conducted at the MPIL served this goal. Mosler explicitly acknowledged that the Institute’s foundation was motivated by ‘the struggle against the Treaty of Versailles, which was perceived as unjust’. ‘The legal means provided for in the treaty itself were to be exhausted.’ ‘The Institute owes its existence largely to the need to take part in the struggle with solid international legal arguments based on an extensive documentation.’ Yet, according to Mosler, ‘the Institute was not an auxiliary instrument of the Reich-government, but an Institute committed to basic research’, tasked first of all with collecting the necessary materials.50
Bruns’ article made explicit the Institute’s task of collecting and systematising the material, but avoided overtly presenting international law as a weapon for Germany. Yet, the purely German perspective is painfully obvious in the foreword of the newly founded journal. Here, Bruns identified as the ‘main contemporary problems’ the reparations issue, the interpretation of peace treaties, [and] the problem of [German] minorities’.51 Globally, these were not necessarily the most important problems of the international law of the time, but they were in fact the most pressing questions Germany was faced with. Bruns’ manuscript of a lecture entitled ‘International Law as a Legal Order’ (‘Völkerrecht als Rechtsordnung’), on which Bruns’ article was based, reveals this posture plainly.52 The manuscript concludes with the words: ‘I think us Germans have everything to hope for from a victory of law, and nothing to fear.’
Mosler stood up for German interests as well. Reflecting on the post-war period, he identified the Institute ‘main goal’ as ‘regaining a position in the international discourse’.53
Ultimately, the research programmes of both directors (and thus that of the Institute) was shaped by an intense epistemic nationalism. This was largely due to the parallel circumstances both directors faced: a German state defeated in a world war, weakened as a state, even regarded as a pariah among nations, struggling to regain its place in the community of civilised nations. In this context they sought to use international law as a weapon—lawfare for Germany.
5. Bruns’ and Mosler’s Achievements
a. Viktor Bruns
While Bruns was drafting his article, new trends in other fields emerged which would later become highly significant for international law and scholarship. The Muslim Brotherhood, whose offshoot Hamas is today designated as a global terrorist organisation,54was founded in 1928. In the same year, Margret Mead published Coming of Age in Samoa, a work that would later become important in debates on cultural relativism and legal pluralism.
Bruns, given his academic and social connections, was likely aware of the spectrum of contemporary intellectual trends in the humanities and social sciences.55 Yet, he deliberately opted for a strictly doctrinal approach, eschewing inter- or transdisciplinary contextualisation or methods. This was also what Mosler appreciated. He regarded Bruns’ argument for the coherence of the international legal order constituted ‘through rational argumentation and state practice’ as ‘one of the main achievements of Bruns’ work’.56 Mosler saw this as a ‘progressive idea for the time’.57 With this idea, Bruns had positioned himself against ‘the contemporary proponents of the doctrine of absolute state sovereignty’.58
Even today, some voices in the (German) literature tend to follow Bruns’ position, ‘derived’ from the nature of international law as a legal order, that the states are competent to act on the international plane or with extraterritorial repercussions only when international law allows this.59 By contrast, in its Kosovo-opinion, the ICJ reverted to the Lotus-style presumption that states are free to act, also with extraterritorial effects, if not specifically prohibited by international law.60
Bruns did not address key international law issues that were emerging in 1929 and remain central today: the prohibition of the use of force was absent in his article, despite the Briand-Kellogg Pact coming into force that year. He did not mention international humanitarian law, although the Red Cross movement was formalised in 1929, and two Geneva Conventions were signed in the same year. Bruns did not even discuss human rights despite certainly having been aware of the Institut de Droit International’s ongoing work on a ‘Declaration of the International Rights of Man’, published on 12 October 1929.61 Bruns made hardly any mention of the League of Nations either, except in the context of a lengthy discussion of the domaine réservé.62 His article lacks any reflection on the potentially innovative character of this young international organisation and its work.63 Bruns was not committed to the ‘Geneva spirit’.64 Thus any later critique of interwar international law scholarship as naively idealistic does not apply to him.65 It seems fair to conclude that his lasting achievement lies in his initiative to collect the international law materials, and to engage the entire Institute in ordering and rationalising this material, and with it the entire field.
b. Hermann Mosler
Mosler was more innovative and more of a visionary. He was one of the first scholars to register the ‘extension of the circle of international legal persons’ and was able to analyse this development in doctrinal terms.66 He reached an international audience with his lecture on this topic in The Hague.67
Mosler progressively qualified the right to self-determination as a ‘peremptory norm’.68 This might have to do with the fact that this principle was central to the legal discussion on the international legal status of the Federal Republic of Germany and the ‘German question’. Only 48 years later, the ICJ qualified the right to self-determination as ius cogens in its Advisory Opinion on Palestine.69
In contrast, Mosler did not ascribe any jurisgenerative quality to resolutions of the UN General Assembly. Rather, he perceived the ‘danger that politically motivated majorities may convey an unrepresentative picture of the opinio iuris’.70 He thus remained considerably more cautious than colleagues (whom he avoided to even quote), who had already attributed some normative relevance to these resolutions years earlier.71
Finally, Mosler was miles away from the post-colonial world view that colleagues from the Global South were advocating for at the time. The ultimately failed attempt by the Global South to establish a New International Economic Order (NIEO) went completely uncommented, at least the 1976 article. Mosler did not mention the relevant General Assembly resolutions,72 but only the Charter on Economic Rights and Duties as ‘the best-known example’ of the contemporary General Assembly resolutions which ‘express tendencies towards a further development of international law’.73 It is therefore hardly surprising that Mosler remained unfamiliar with any criticism of a ‘neoliberal’ international legal order which had already been voiced by French colleagues.74
Mosler expressed reservations about the new states of the Global South, which he considered to be ‘territorial entities with unsecured viability’75 that ‘disrupt’ ‘the picture of the extant community of states’.76 Anti-colonialist international law experts were present at the MPIL as visiting scholars at this time. Perhaps Mohamed Bedjaoui even prepared his Hague Lecture here, in which he criticised the existing international legal order as Eurocentric, neo-colonial, imperialist, and oligarchic.77 Mosler apparently did not consider this critique worth mentioning. He could not see the current preoccupation of international legal scholars with colonialism coming, nor anticipate the thesis that colonialism has been constitutive for international law as a legal order. It was probably impossible to foresee that the colonial legacies in international law would be exposed, that the ideas of the NIEO would be rehabilitated, and that calls for reparations for slavery and colonialism would emerge in the new millennium. The Eurocentrism of the directors and the Institute they headed was in the academic mainstream of their times.
6. International Law as a Legal Order 2025
Beyond their individual achievements, is Bruns’ and Mosler’s approach to international law still relevant today? Or has the overarching question whether international law is a legal order become obsolete?
a. A World Order in Flux
Since Mosler’s time, over fifty states and four billion people have joined the international legal order, demanding a greater role in shaping it and a stronger consideration of their needs, interests, and values. On top, thousands of international organisations, civil society actors, transnational corporations and criminal and terrorist networks have emerged as influential players. In 2025, the political programme of a China and Russia-led anti-liberal alliance for a ‘New World Order’ is openly articulated.78 These actors have transitioned from mere takers of international law to shapers of it. They aim to establish order, and this shall be a new one, different from what we have been used to. The buzzwords of a ‘post-Western’, ‘post-liberal’, and post-American order encapsulate this shift.79 Is a parallel search for order in international legal scholarship still meaningful? This question arises in the context of a profound legitimacy crisis of the current international legal order, driven by new ideas and changing interests, and unstable power structures.
b. Bruns and Mosler as Practice-Oriented Lawyers
In this era of upheaval and realignment, there is a pressing need for critical (disruptive), approaches to international law, perhaps more than for conformist (enabling) contribution.80 However, Bruns’ and Mosler’s scholarship exhibited a tendency towards the latter, conformist, practice-accompanying and -enabling type of international law scholarship.
Firstly, according to Bruns and Mosler, arguments had to be system-conforming in order to be accepted as valid. Their efforts to establish the orderliness of international law were exercises that were situated inside the law as an intellectual edifice. For Bruns, this exercise took the form of ‘proving’ the absence of legal gaps and identifying (‘necessary’) general legal principles.81 Mosler pursued the same goal by referring to ‘constitutional elements’, to ius cogens82 and with the creation of a doctrinal foundation of international legal personality.83 Both saw the task of international law scholars as working with the international legal system, by way of interpretation (analysing the meaning of norms), exposing the legal principles underlying the specific rules, pointing out ‘logical’ contradictions, and filling gaps. All this was to be done with the help of the entire doctrinal toolbox, in order to identify, uphold and safeguard the international legal order. To some extent these scholarly moves even co-created such order.
The second shared characteristic is both Bruns’ and Mosler’s focus on legal practice. Both peculiarities, the scholarly efforts to uphold an ‘order’ or a ‘system’, combined with a strong orientation towards legal practice seem—at first glance—to make the articulation of critique (ie the first dimension of scholarship mentioned above) more difficult. Rightly, Sué González Hauck observes: ‘The notions of system, order, and coherence significantly contributed to relegating the Third World’s attempts to reshape international law to the political realm, and allowed to counter those attempts with ostensibly neutral and legal arguments, that just so happened to preserve Western dominance’.84
In response to this valid comment, I suggest that the conservatism and status-quo preserving tendency of Bruns’ and Mosler’s approach to international law can be mitigated by slightly modifying and complementing their research programme. I will show that, when supplemented by further reflection, their original research programme can be upstepped to satisfy contemporary needs for an effective, constructive, and even transformative scholarly critique of international law.
c. Ordering the Law as a Precondition for Effective Legal Critique
The starting point of my argument is that any critique of international law (be it realist, constitutionalist, Marxist, ecological, neo-materialist, or any other) originates from outside the legal system. It is a task of scholars to ensure that international law does not become a mere plaything of these critical movements. Put differently, legal scholars should reformulate the critique in a way that ‘stimulates transformations from within the legal system in order to expose the contradictions between the legal order as it is and the demands of [global] socio-economic justice and thereby to mitigate the violence of the law’.85
At this juncture, the scholarly establishment of legal order, as advocated by Bruns and Mosler, can serve as a bridge between the external and the internal critique, and thus render the critique of international law (a critique that we need in current times) more powerful. Such a combination (mediation or ‘dialectic’) of the two modes of critique has more force than either a critique articulated solely from an external standpoint or a critique formulated entirely from within the legal system.
To explain: On the one side, any critique of international law from the outside (based on paradigms that might range from rational choice to post-colonialism or whatsoever) cannot lead to changes of the law unless it is integrated into the law itself, and this can be done only by translating the political positions into legal arguments. Moreover, any critique of the law relying only on some external benchmark of morality or political ideology will be to some extent random. On the other hand, a purely internal critique (working inside of the doctrinal parameters), has no teeth because it is itself socially and historically contingent, remains within an unquestioned horizon of values (has ‘blind spots’) and tends to preserve the status quo. It is inherently conservative because it must treat certain legal parameters as a given, indeed as dogma. Because both approaches have shortcomings, they can be usefully combined to complement each other and fill the gaps. Critique of the law can become more powerful when it argues both from within international law and from the outside.86
Bruns’ (and in a mitigated form also Mosler’s) approaches were confined to the internal realm of the law and therefore had little bite, as explained above. Another blind spot of especially Bruns’ scholarly approach was that—by remaining internal to the legal system—it implicitly presupposed that the ordering of the law would contribute to order in the real world, too. Yet, it is debatable whether, to what extent and how international law is conducive to the stabilisation and pacification of international relations. Generations of political scientists working in a ‘realist’ paradigm that focuses on power politics in international relations have doubted that law is a force of order at all.87 The opposing positions that reject such power-focused realist paradigms are exemplified by the ‘Peace Through Law’ Movement, which emerged at the end of the 19th century and motivated the Hague Peace Conferences, the founding of the Hague Academy of International Law, and the establishment of the League of Nations.88 The efforts to build an international law which, by power of its own orderliness, is able to create order in international relations, are by no means a thing of the past. They shine up in the debate on the fragmentation of international law at the beginning of this millennium and in the International Law Commission’s (ILC) ongoing work on all (traditional) sources of law. Especially the search for general principles is an evergreen, and the ILC Draft Conclusions on General Principles (2024) explicitly assign to these principles the function of fostering legal coherence.89 Against such attempts of generating order through law, objections from an external perspective have been raised not without merit: Any ‘ordering’ of international law in the service of coherence does not guarantee the fairness of this order. Quite to the contrary, one could say that the preservation of the status quo serves the privileged members of the ‘legal community’—which are currently, in oversimplified terms, the states of the Global North and the Great Powers.90
In response to this well-founded critique from the outside of the law, I would like to offer a perspective on a middle ground which mediates between the external and the internal perspectives: First, legal stability can be said to also benefiting the small, poor and weak states (at least) to the extent that such stability avoids the chaos, violence, and suffering that often accompany legal upheavals, as historical experience teaches us. This is why the principle of uti possidetis, for example, establishes a legal presumption for the immovability of state borders, regardless of how arbitrarily and violently these borders had been created.91
Secondly, the orderliness of law is likely to generate a weak form of legitimacy which flows from consistency (the absence of internal contradictions, including on values). This rather formal virtue can maybe persuade those subjected to the law to accept it as fair, and this in turn can contribute to better compliance and thus to an overall greater effectiveness of the law. The conservatism inherent in the search for legal order notwithstanding, a deeper reason for this search for order is that any incoherence in the legal system runs counter to a basic postulate of justice, namely the (formal) justice that lies in avoiding internal contradictions. As Mosler put it: justice ‘is necessarily linked to the concept of a legal order’.92 It is exactly owed to this link between order and justice that the current accusations of ‘double standards’ (however well founded or not they may be) resonate so much.
Third, an orientation towards legal practice, as pursued by Bruns and Mosler, makes sense even for a reason that Bruns and Mosler might not have had in mind. This reason is that, in order to live up to the critical aspiration to not only interpret the world but to change it, and to help improving the fate of concrete human beings, any critique of the law must be informed, complemented, and challenged by a (critical) practice.93 For all this, a solid knowledge of the positive law, as applied, is indispensable.94 Along this line, critical and TWAIL approaches have recently been blamed for their detachedness from practice. More involvement of critical and TWAIL lawyers in the practice of international law seems warranted in order to actually contribute to the law’s alignment with the interests of the populations of the Global South.95
In the midst of these debates, and facing the current turmoil in world politics and international law, the academic programme of ‘International Law as a Legal Order’ is almost fit for 2025. It would need to be strengthened by an external-critical perspective, as described, without having to give up neither its practice-orientation nor its doctrinal-internal perspective. This means that unless life on our planet does not end before, the ordering of law as a contribution to achieving order through law is a valid task of the MPIL for the next 100 years.