A world safe for Catholicism: interwar international law and Neo-Scholastic universalism

ABSTRACT This article recounts how Neo-Scholastic international lawyers navigated the complex political landscape of the 1920s and 30s, combining universalism, nationalism and religious belief. Participating in the contemporary re-engagement of Catholics with modern politics, they re-imagined the international legal order in Catholic terms. They argued that a universal morality, overruling the extremes of state sovereignty, was the only solid basis for just and stable global legal relations. While the contribution of Catholics to the establishment of the post-war world order and the rise of human rights is widely acknowledged, the interwar genealogy of these developments is not. Reading these thinkers’ universalist legal tenets in conjunction with their political trajectories provides a relevant frame to understand the moral charge characterizing international law in the early years of the Cold War.


Introduction
This contribution outlines the concept of universalism as developed by the leaders of the Association Internationale Vitoria-Suarez in the interwar years. International lawyers such as James Brown Scott, Louis Le Fur, Yves de La Brière and Alfred Verdross seized on the larger Neo-Scholastic trend ongoing within Catholic culture to rethink the foundations of the international legal order. Inspired by the thought of Thomas Aquinas and, especially, by his early modern Salamancan followers, they sought to move beyond positivist legal theory and sovereign will as the only source of international law-making. They argued that a universal morality, founded on the concepts of person and international community, was the only solid basis for just and effective global legal relations.
Their common conceptual effort to reconstruct the universality of international law along Scholastic lines after World War I was part of a larger Catholic engagement with modern politics, seeking to envision a properly Catholic social order for the twentieth century. 1 This re-engagement operated throughout the various institutional and social expressions of Catholicism and gave rise to diverse and often divergent intellectual approaches. At a central institutional level, it manifested itself in the Vatican's international policy through Concordat diplomacy and the anti-communist campaigns of the 1930s. 2 However, the most wide-ranging and articulated ideas and proposals came from Catholic academia and public intellectuals. Initially they sought what they called a third way beyond socialism and free-market democracy, both considered ills of a materialist modernity. Later on, this effort to create the space for genuine Catholic politics in modern society evolved to face the changing European political landscape of the 1930s. Catholic thinkers understood Bolshevism and Nazism as natural evolutions of modern secular politics, similar in their demand of exclusive allegiance. In response, they conceived an early theory of anti-totalitarianism. 3 Despite this, then and throughout World War II, sections of the Catholic Church and its faithful collaborated with fascist or authoritarian regimes, including that of Nazi Germany. However, at least at the level of argumentation, the collaboration was not based on adherence to fascism as a political doctrine. Catholics sought to retain the widest autonomy over freedom of worship, family matters and education. Most were ready to sustain the right-wing regimes that provided such space and fought the common enemy of communism.
The reckoning with modernity of Catholic political and social thinking tapped into both internal and external intellectual resources. It claimed the legacy of Scholastic theology, anchoring itself to the authority of established Catholic tradition. However, it also increasingly adopted the methods of social sciences and opened itself to secular doctrines, moving gradually from rejection to engagement with the newest ideas and trends in the larger society. The negotiation between Catholic tradition and secular modernity also framed the debate internal to the movement. The various approaches ranged from neo-medievalist responses, seeking a return to the values and hierarchy of the sacralized order of the Respublica Christiana, 4 to thinkers proclaiming the compatibility of a Catholic social order with liberal-democratic regimes, eventually adopting a language of individual rights.
This article reads the revival of early modern Scholastic theologians among interwar international lawyers as belonging to the contemporaneous renewal of Catholic political culture. The reclaiming of Vitoria and Suárez by international lawyers is normally explained away with its connection to the simultaneous interwar resurgence of natural law within the discipline. While the relevance of the link is patent, assessing how and how much both phenomena have been related to Catholic thought could shed further light on their nature and their later incarnations. Indeed, in recent years, several scholarly works have appeared unearthing the Catholic role in key post-World War II developments in the international order, such as the rise of human rights language and the early steps of European integration. 5 Other recent studies have provided deeply researched accounts of the renewal of Catholic socio-political culture, 6 the Neo-Scholastic intellectual tradition 7 and the Holy See's foreign policy in the first half of the twentieth century. 8 Yet, to the best of my knowledge, no study has focused on analysing the work and ideas of interwar Catholic international lawyers within that context. 9 This text represents an initial attempt to open such a line of research. Focusing on Catholicism and international law in the interwar years, I submit, provides a uniquely valuable vantage point to deepen our understanding of the historical development of the legal concept of universalism. Indeed, it portrays the intersection of two discourses and epistemic communities that had traditionally been at the forefront of articulating universal aspirations through legal argumentation in the West. Moreover, this was occurring at a time when the equation of European culture as the absolute global standard of civilization was being put into question for the first time in the modern era. The Scholastic revival represents a helpful framework of analysis of the different strategies and responses Catholic international lawyers adopted to face the interwar crisis of universalism.
The protagonists of this article combined the intellectual resources of their religious background and the milieu of their discipline to search for a path of stability for the international order. As it turns out, their brand of universalism had elements of both inclusion and exclusion. In the former mode, it opened the space for a pragmatic compromise with the internationalism of conservative liberals, finding common ground in the construction of global institutions as a tool to sideline subjective state will in favour of an objective vision of justice, all the while seeking to re-establish a Catholic cultural hegemony. The directly exclusionary elements were more marked. To begin with, this universalism was not universal at all. It intervened in a battle for legitimate authority in Europe (or, at most, in the West). The rest of world, apart from paternalist and often openly racist justifications of colonialism, was beyond its horizons. Within Europe, the claim to be interpreters of universal morality, able to save the global order, was routinely weaponized to indict opposing entities and doctrines, defined as detrimental to the flourishing of humankind. This weaponized legal universalism was rather versatile and routinely applied to rivalries between nations, religious controversies and internal political struggles against the left. Specifically, this article focuses on how the leaders of the Association Vitoria-Suarez translated interwar Catholic universalism into international legal doctrines by conceiving compulsory principles of objective justice and a wider vision of legal personality.
Through this endeavour, Neo-Scholastic international lawyers 10 participated in the mutually constitutive and irreducible conceptualizations of religion, nationalism and internationalism that characterized the political discourse of the time. As Nathaniel Berman has made clear, the interwar discourses 'taking seriously … the dangerous proximity between the sacred and the profane' 11 are still relevant and instructive for our time. Indeed, while the narrative of secularization persists, notably in the managerial discourse of institutional actors, our politics clearly include visions of a sacred universal, which mix and blend in multifaceted ways with nationalist and internationalist arguments. Looking to the interwar years, when attentiveness to the crucial importance of this three-sided relationship to fundamental questions of political ordering was more explicit, could give a better grasp of our present dilemmas.

Universalism and international law in the interwar years
A constant feature of the political and legal discourse of the last century is, on one hand, claims that universalism is in crisis and, on the other, renewed universalist projects that aim to overcome that very crisis. International law and universalist aspirations are inextricably intertwined. In its various historical iterations and formulations, international law has rested on the assumption that it represents a legal order operating at a global level and binding on the whole of the human community. One could say that universality is a basic concept of international legal discourse, a fundamental building block. Of course, this enduring relationship has manifested itself in a constant flux and state of ambivalence. As theories and practices of international law changed over the course of history, so did the foundations of the various universalist projects that were articulated through them. By the late nineteenth century, the universalist paradigm that had founded the law of nations on natural law and its theological presuppositions since the early modern period had been left behind. The universality of international law was now embodied in the confident Victorian rationalism of the rising professional class that claimed to be its experts. In the climate of legal positivism of the era, international lawyers described a system originating from the will and behaviour of sovereign states but nonetheless coloured by their liberal world-view and belief in progressive reform. 12 At the act of foundation of the Institut de droit international in 1873, the international legal profession, represented exclusively by Western white men, claimed to embody 'the legal conscience of the civilized world'. 13 The rupture of the Great War exposed the fragility of the international legal project, its inability to stand in the way of military escalation and its lack of functionality in the face of the excesses of imperialist exploitation. Nineteenth-century dreams of universal progress came to embody the hubris and delusion that had led Europe towards self-destruction. Yet, as it is often the case, the sense of loss and crisis became the breeding ground for new approaches and ideas. International lawyers, already while the conflict was still raging, began calling for their discipline's reconstruction 14 but could not rely on the conceptions prevailing before the war. The interwar years became a laboratory for a series of projects conceiving of worldwide relations through law. Notwithstanding the crisis of universal reason, these projects did not sever the link between international law and its global aspirations. On the contrary, several of the attempts at renewal went in disparate directions seeking universal foundations beyond pre-war positivist legal theory.
In particular, key members of the Association Internationale Vitoria-Suarez sought a break with the legacy of the nineteenth century by looking further back in the past. They came together to reconnect international law with its Catholic natural law foundations. This enterprise was part of the larger Neo-Scholastic movement that represented a Catholic cultural response to the perceived self-destructive lack of morality in modern society. It was also part of the wider and multifaceted reaction among legal theorists against positivism and legal dogmatics, considered as having disconnected law from justice.

Neo-Thomism and the inception of the Association Internationale Vitoria-Suarez
The widespread revival of Thomist theology in Catholic circles was not a new phenomenon in the interwar years. 15 It had originated already in the second half of the nineteenth century as a defence against secular ideologies and the increasing encroachment of European nation states on the Church's centuries-held privileges. Its adoption by the Holy See represented an early engagement of Catholic doctrine with modern society, moving one step beyond the mere condemnation during the papacy of Pius IX.
In 1870, following the annexation of Rome to Italy, the State of the Church had ended its millennial existence. Pope Pius IX declared himself a prisoner on the Vatican hill. In 1879, his successor Leo XIII issued the encyclical Aeterni Patris, which exhorted Catholics to spread the medieval philosophy of Thomas Aquinas (1225-1274) as the 'bulwark of faith' against the modern 'plague of perverse opinions'. 16 Aquinas's unmatchable articulation of the harmony of reason and faith would protect the 'minds of students' from 'prevailing errors' and work 'for the good of society, and the advancement of all sciences.' 17 The papal appeal sought to establish Thomism as a solid doctrinal basis for a fortress Catholicism, to fight modernity outside the Church and modernism within its ranks. Leo XIII had encouraged a trend that would soon characterize Catholic culture worldwide, spawning a dynamic and diverse movement. The varied ways in which Catholic intellectuals negotiated their relationship with the authority of Aquinas and their understanding of the Scholastic tradition produced significant debate and even controversy. 18 At this stage, most internal confrontations belonged to the spheres of theological and philosophical speculation, but soon they began spilling over into issues of law and politics. Indeed, Neo-Scholastic thinking did not always remain confined within the strict lines favoured by the Vatican, initially opposing any form of modern politics as such. For example, the revival reshaped Catholic education and intellectual discourse in the United States, where it acquired a peculiar local character. Americanist clergymen sought to articulate the harmony of the liberal-democratic political culture of the United States with Catholicism, often with reference to the Scholastic tradition. 19 It was within the context of US Catholicism that James Brown Scott, the initiator of the Vitoria-Suarez Association, developed his Neo-Scholastic brand of international law. Curiously, Scott was not a Catholic. He had been raised as and remained for his whole life a Protestant, a Presbyterian. His immersion in a Catholic academic environment, which sharpened and directed his reception of the Salamanca School, dates to 1920 when he joined Georgetown University, a Jesuit institution. Yet, his fascination with the Catholic Church and the crucial role he reserved for it in international law shone already through his first public speech in 1896. Therein, he argued for a return to the medieval custom of entrusting the Pope, as the only legitimate representative of a universal morality, with the arbitral authority to solve disputes among states. 20 At first look, the Association Internationale Vitoria-Suarez Scott initiated may seem like one of the many loose thematic sub-groups of academics sharing a specific interest within a larger discipline. Indeed, the Association was established during an informal gathering in Cambridge, a side event to the 1931 meeting of the Institut de droit international. However, at least in Scott's mind, this was to be part of a larger movement and paradigm shift in the understanding of global relations.
Scott had been a major actor in the rise of international law as an academic discipline and tool of government in the United States. International law's newfound role coincided with the rise of the self-awareness of the US as a global power. The connection of these two developments was embodied in the Scott-led 1906 foundation of the American Society of International Law. Asked for a comment on the reasons behind the creation of the new Society, its Vice-President and soon-to-be US Secretary of Commerce Oscar Straus would declare: 'We are a world power and we must put on world-power clothes to meet the situation.' 21 Scott's case for a new US-inspired conception of international law was based on his nation's argued exceptional character. It had, as well, a crucial universalist element. The rising global leadership of the United States, with its social order based on formal law and equality, would bring about a new, fairer international law. Global relations would be based on justice and guarantee the rights of each state, including the smallest and least powerful. 22 In the interwar years, Scott added historical layers to his argument. The historical narrative that came to characterize the last few decades of his career was what he called the Spanish origin of international law. Two early modern theologians of the Salamanca School were responsible for the establishment of modern international law. In the mid-sixteenth century, Francisco de Vitoria, by recognizing dominium (the rights of sovereignty and property) for the natives of the newly discovered American continent, 23 had conceived a global law based on equality. A few decades later, Francisco Suárez, by clarifying the connections and the distinctions between ius gentium and natural law, had given international law its main philosophical tenets. This meant moving the context of the foundation of international law from the European wars of religion, which had prompted the writing of Grotius' magnum opus, De jure belli ac pacis (1625), to the discovery of the American continent. Even more crucially here, it meant denying a Protestant fatherhood and placing the birth of international law within the Catholic theological tradition.
For Scott, his enthusiastic celebration of the Salamanca School represented three main developments. First, the justification for the global hegemony of the United States as the harbinger of the new and morally improved global law; second, the affirmation of justice in international relations over mere state interest and power; finally, the recognition of the legacy and crucial contemporary relevance of Catholic thought for imagining the future of international law in the twentieth century. The score of renowned international lawyers who joined him all shared the second aspect of the equation. A majority, men of Catholic faith, also shared the third. In addition, all came to the project with their own backgrounds, theories and agendas.
The list of founding members of the Vitoria-Suarez Association in 1931 reads like a 'who's who' of the scholars seeking to move beyond positivism through naturalist and sociological approaches to the discipline in those years. It reached beyond Catholic circles. However, for the non-Catholic scholars, participating in the revival of the Spanish Scholastics appears to have been a shallow cultural interest or a minor token of their larger commitment to overcome positivism and reconnect international law and society.
Instead, for the overwhelming majority of the membership of the new association, claiming the legacy of Vitoria and Suárez meant an intense engagement with the natural law tradition in deep connection with their religious experience and political commitments. This group included the initiator of the association, James Brown Scott. Notwithstanding his long-standing respect for the moral authority of the papacy and established intellectual association with Scholastic theology, as a Protestant, Scott was an exception. The committed membership of the association was otherwise entirely made up of devout Catholics. Among them were Scott's Spanish collaborators who had founded a national Asociación Francisco de Vitoria already in 1926: Camilo Barcia Trelles, Aniceto Sela y Sampil, José de Yanguas Messia and Joaquín Fernández Prida. Others included Gabriele Salvioli, who, with his tendencies towards natural law, was an outlier in the Italian international law community, dominated by the strict positivism spearheaded by leading figures like Dionisio Anzilotti and Tomaso Perassi; 24 the Belgian de Visscher brothers: Charles, a future judge at the World Court in both its pre-and post-war incarnation, and Fernand, the renowned Roman law scholar.
The de facto leadership of the association belonged to an even more restricted group of members, informally directed by Scott. This included two Frenchmen previously involved with the Action Française and active in monarchist circles: the Jesuit Father Yves de La Brière and Louis Le Fur, professor of international law at the University of Paris. 25 As secretary of the association, Scott placed Alfred Verdross, the Viennese former student of Hans Kelsen. To begin fleshing out the connection of the international law revival of Scholasticism with the larger interwar Catholic discourse, the remainder of the article will focus on the work of these four figures sharing the leadership of the Association. Their common project of recasting international law as a universal order took different shapes and meanings according to their respective contexts and background as they navigated the tumultuous politics of the time.

International law and the Catholic Universalist tradition
The renewed popularity of early modern Spanish theologians among interwar international lawyers did not always mean close engagement with the intricacies of their Scholastic thought and way of argumentation. As a wider project, the revival embodied a reaction against abstract theories of sovereignty and a yearning to reconnect international law with the factual experience of human relations.
Among Neo-Scholastic scholars this yearning took the form of an emphasis on the wisdom of tradition, embodying the common good of mankind as the ultimate end of law. 26 However, Neo-Scholastic international lawyers did not argue for throwing the baby of the achievements of positivist legal theory out with the bathwater of their ultimate detachment from social reality and human nature. They developed what they often called synthetic theories of international law. 27 Largely, they left the formal structures of the discipline in place, but they reconstructed those structures on natural and moral foundations, 'preceding the will of man and imposing themselves over it'. 28 Neo-Scholastic international lawyers agreed that the foundations of international law lay in a universal morality, a sense of objective justice uniting all mankind. 29 Their common identification with the legacy of Vitoria and Suárez was a celebration of the establishment of the modern discipline and the relations between peoples on that concept. 30 The two Spanish theologians had managed to save the universalist conception of the Respublica Christiana in the Middle Ages, beyond its disaggregation in the face of the Reformation and the early rise of nation states. The division and differentiation of human institutions and communities could not deny and overcome the fundamental moral and political unity of mankind.
The state superiorem non recognoscens nonetheless belonged to a universal community and was bound by its norms of cooperation and interdependence. Later attempts to found international law on an absolute doctrine of sovereignty had not only led to the tragedy of the Great War but also failed to establish a coherent theory. For instance, positivist scholars like Anzilotti and Kelsen had based international law on the principle pacta sunt servanda, affirming the obligation of states to uphold agreements they entered. However, this was a principle of natural law, valid priorly and beyond its acceptance by state entities. It was a basic expression of the moral sense shared in the international community embracing all mankind. Indeed, pacta sunt servanda had already provided the foundation for the ius gentium of early modern Christian naturalists like Suárez and Hugo Grotius. 31 In logical terms, international law could not stand on the mere consent of states. Building on this revisionist narrative of the history of international law, the Neo-Scholastic international lawyers of the Vitoria-Suarez Association proceeded to discard the horizontal and voluntarist basis of positivist doctrines. Their revamped universal legal order was expressed through three main, interrelated directions.
Firstly, they envisioned international law as a hierarchical normative order. Principles embodying the objective dictates of humankind's shared morality would enjoy a higher status than basic rules. For instance, in the interwar period Alfred Verdross produced the early articulations of his constitutional theory of international law 32 and of the doctrine of jus cogens, a set of compulsory norms based on the ethics of the international community. Deviation from jus cogens, the argument went, would be contra bonos mores and have the effect of making a treaty invalid. 33 After World War II, Verdross would develop these themes further, establishing his legacy in legal thought up to this day. 34 Secondly, they advocated the explicit incorporation of moral considerations into the application and enforcement of international law. 35 This entailed, crucially, a return to the just war doctrine that Vitoria and Suárez had famously articulated. Indeed, if war was simply an attribute of the sovereign state as held in pre-war international law, international relations were ultimately based on mere force. War, instead, was necessary but to be pursued only according to the justice of its cause. In its bellum justum form, war represented the restoration of the moral integrity of the international legal order. A recurring theme through which Neo-Scholastic international lawyers incorporated just war thinking in their legal analysis was that of humanitarian intervention. 36 Thirdly, they conceived of international legal personality as open to entities other than states. Their hierarchical understanding of the international order led them to be favourable, in the abstract, to moderate forms of global federation, intended as an institutional embodiment of humankind's common morality. A distinctive feature of the pluralist understanding of international legal personality among Catholics was their arguing in favour of a special type of spiritual universal sovereignty international law was to recognize to the Holy See. 37

Neo-Scholastic Universalism, nationalism and Catholic interwar trajectories
The overarching narrative of the Neo-Scholastic revivalists hinged on the basic tenets just described. International law could be a force for the common good of humankind if founded on the higher principles of morality all humans shared. The relationship of universal morality and global law had been best captured in the Catholic theological tradition. Vitoria and Suárez in particular had been able to articulate international law as responsive to both the dictates of human conscience and the autonomy of civic communities. Already on its face the universalism of interwar Neo-Scholastic international lawyers was highly particularistic. The universal morality they invoked as saviour of the global order coincided with the morality associated with their Catholic religious faith. 38 However, the complex identity negotiation that shaped the group's worldview, their political action, and scholarly doctrines did not rest merely on legal universalism and Catholic belonging. All of them linked their overall vision to some form of nationalist politics, extolling the moral superiority of the culture of their respective countries.
Throughout the interwar years, Louis Le Fur identified Catholic universalism with the traditional values espoused by the French nationalist right. In his scholarly work, the identification relied heavily on a symmetrical opposition with and an indictment of German legal doctrines and their foundations. 39 Right after the Great War, in 1920, Le Fur penned a book reading the conflict through the lens of just war theory. 40 To explain why Germany had started an unjust and criminal war of aggression, Le Fur tracked a line of thought dismantling tradition and the objectivity of good back to Martin Luther and reaching to contemporary thinkers through the philosophy of Immanuel Kant. The subjective morality running through German thought developed into a limitless adoration of the nation state, Le Fur argued. On the international plane, this meant absolute sovereignty and no necessary justification for war other than power.
A few years later, Le Fur rejoiced over the work of thinkers in the German-speaking world who sought, as he put it, 'to ditch the narrow and negative doctrines that had dominated [there] in the previous century'. 41 42 In these works and other interwar ones, Verdross's reliance on the universalist conceptions of the Scholastics is explicit. 43 It is through Vitoria and Suárez that he affirmed the relation of the moral unity of humankind with the global unitary legal system of international law and its hierarchical normative ordering. The Scholastic foundation of Verdross's international constitutionalism is often noted in the literature on his legal theory and legacy. Nevertheless, it is usually labelled generically as a naturalist approach and rarely delved into as an expression of his Catholic faith and politics. In an exception to this trend, Anthony Carty has drawn a direct connection between Verdross's Scholastic approach of the twenties and the politics behind his Völkish international law of the late thirties. 44 Verdross's pan-Germanic nationalism and somewhat qualifiedapproval of the Italian Fascist and German National Socialist regimes appear to be founded on what he considered the primary goal of politics and international law: the defence of Catholic values.
In March 1938, a few days before Germany annexed Austria, he explained the necessity of cooperating with moderate Nazis: it would 'assure […] Christian leadership in Austria'. In turn, this would be a step towards his ultimate political goal: 'the melting of all good Austrians into a Christian German People'. 45 In the first edition of his international law textbook, Völkerrecht, published a year prior, he had praised Mussolini as a guardian of the tradition of Catholic values and Nazism as an anti-imperialist and federalist ideology. 46 Like most Catholics at the time, Verdross favoured the two regimes as bulwarks against communism and because of the privileges and guarantees they accorded to the Catholic Church. 47 These derived from Concordats, international agreements the Holy See had signed with Italy and Germany, respectively in 1929 and 1934.
Verdross tried to build on these political affinities through his scholarship. In Völkerrecht, he sought to bring Nazi doctrine and his Catholic-inspired universalist international law closer at a conceptual level. At the same time as he was extolling the binding force of the morality of the international community of humankind through jus cogens norms, Verdross connected the Aristotelian (and Scholastic) idea of civitas perfecta with that of Volkstum (national identity). 48 Carty interprets the paragraph titled Volk und Staat in which Verdross explores this latter connection as entailing three elements: 'The individual man exists only as a member of a people; the goal of a peaceful international order is to ensure that each people is able to build its own state; and it is the state and the international legal order's function to serve the well-being of peoples, and not vice versa.' 49 Now, I submit, the nod to the Nazi apparatus was not primarily in this affirmation of doctrine, vague enough to elicit a number of potential intellectual associations. It was in the context of the book, where the Volkstum passage follows by just a handful of pages Verdross's praise of Nazi anti-imperialism, and, especially, in the choice of language. To be fair, Verdross's body of work is devoid of biological reasoning and also in this case he stopped just short of adopting a racial theory. Yet, his words on human diversity here were particularly 'suggestive': There are no human beings as such, only human beings of a certain kind. The highest natural human species is the 'Volkstum' (national identity), […] the natural foundation of all culture. The state needs to reflect this state of affairs in its political setup, […] but can only perform this function if it allows its citizens to thrive according to their natural capabilities and character. Because of the natural differences between different species of humans, this can only be achieved in the 'Volkgemeinschaft' (in their people).
[…] In their people, humans are naturally connected to other humans of the same species, the state is the political union of human beings under distinctive laws. 50 Le Fur's indictment of German doctrines as the epitome of modern extreme individualism and the main antagonist of Catholic universal values had also been built on accusations of racism. Already in the early twenties, long before Hitler came to power, Le Fur wrote extensively on the connection linking individualist philosophy, legal and political idolization of the state and racist pseudoscience. 51 Reducing all human relations to relations of power, this German Weltanschauung kept leading Europe into war and social chaos. This systematic 'integral nationalism' overlooked humankind's moral nature, which underpinned 'Christianity' and founded 'the universal vocation of all civilized nations to a joint common law, uniting them in its bonds'. It was 'Christianity[,] a religion that […] for the first time […] disregarded all difference of nature, race or language' that 'had made possible international law, a law based on equality between the different races or nations made of human beings equal before the law.' 52 Vitoria and Suárez, Le Fur argued, had been crucial in forging the legal doctrines sustaining the universal common good through the harmony of a healthily conceived state authority and the moral force of the global community of humankind. 53 With the rise to power of the Nazi regime, Le Fur could reaffirm the vindication of his arguments, pointing to 1938 Germany as the most pernicious example of the triumph of the material over the spiritual, of atheist modernity over Christian tradition. 54 Nevertheless, by 1941, Le Fur had thrown his support behind the Vichy regime and his idea of Germany had changed. 55 Nazi Germany had saved Europe from the greatest threats of 'Russian bolshevism' and 'international capitalism, both Jewish and Anglo-Saxon'. The 'global law of the future' would come, he now believed, from the 'European reconstruction', 56 led by Germany and France as 'complementary nations'. France would bring to 'the new regime its profound sense of human dignity'. Germany, with its respect for authority, would help to correct French 'excessive individualism' and 'the universal lie' of 'parliamentary democracy based on universal suffrage'. Only then would there be 'a stable social life' necessary to 'the full development' of a 'human being'. 57

International law and the Holy See: Concordat diplomacy and spiritual sovereignty
Beyond the ambivalent relation with racism, the choices dictated by political convenience and blatant nationalism, there is a clear common stance that emerges from these thinkers' trajectories. The moral and legal concept of universalism underpinning their theory of international law was inextricably linked to the necessity of Catholics playing a leading role and implementing their religious values was considered essential for any society to be functioning and stable. In other words, concrete international legal prescriptions or norms were less crucial than the political and institutional position of Catholics and their Church in modern society. Yves de La Brière was among those who expressed this point in no uncertain terms. A priest and international law professor, de La Brière was the most vocal supporter of the League of Nations among French Catholics. In a 1924 piece praising the activity of the League in its first years, de La Brière diagnosed how it could be even more effective and beneficial. He regretted that the 'secularists and masonic circles' were showing more enthusiasm than the 'faithful'. The ideal development of the League hinged on 'les enfants de la Tradition' taking the initiative, 'making contact with Geneva and having their influence take hold there'. 58 Neo-Scholastic international lawyers, indeed, moulded their discipline in harmony with the larger Catholic strategy. Seeking a pragmatic coming to terms with secular politics entailed upholding a plurality of powers, but not of beliefs. The recognition of the autonomy of natural communitiesranging from global organizations representing humankind universally to more restricted human groups such as families, Churches, associations and local entitiesserved the purpose of protecting the Catholic faith and its institutions from the threat of an all-powerful state. The ultimate means to achieve that was to preserve as much as possible of Catholic influence, values and privileges. An international legal tool crucial to this strategy was the Concordat, a series of treaties the Holy See concluded with various European governments. The content of the Concordats varied. However, they generally contained legal advantages that seemed lost to Catholics since the secularist advances of the late nineteenth and early twentieth century. 59 For instance, they often provided significant financial benefits in the form of tax exemption of Church property and state support for Church activities. They equated the status of Catholic schools with public ones. They provided clergy with legal immunities and instituted the recognition of decisions by Church courts, especially in marriage matters, which would be regulated in key aspects by Canon and not by state law. De La Brière noted that through the 'pactes concordataires' a new 'trend [of] consecrating a good number of important articles of the Code of Canon Law by civil legislation' was becoming 'more and more pronounced'. 60 Moreover, the Concordat strategy had the effect of enshrining Catholic privileges in bilateral acts protected by international law. This ensured that, at least from a formal legal standpoint, national institutions could not independently renege on them. De La Brière could exult that 'the regime of  64 The event prompted Neo-Scholastic international lawyers to reflect on the peculiar nature of the 'international functions of the Holy See'. 65 For instance, James Brown Scott illustrated the agreement between Italy and the Vatican at the annual meeting of the American Society of International Law, a mere two months after its signing. Alongside a Concordat, the Pacts with Italy contained a treaty of more 'traditional' content dealing with issues of territory and relationship among sovereign entities. Most notably, the Lateran Treaty returned the Pope to the status of 'sovereign in the strictest sense of international law': Italy recognized 'the State of the Vatican City' and 'the exclusive jurisdiction' of the Holy See within its 'territorial limits'.
Yet, Scott sought to draw attention to a lesser-remarked reference in the Treaty, acknowledging 'a larger sovereignty possessed by the Pope'. 66 With article 2, 'Italy recognized the sovereignty of the Holy See in the international realm as an attribute inherent to its nature in conformity with its tradition and with the requirements of its mission to the world.' For Scott, this formulation pointed to the fact that the sovereignty of the Holy See was not just 'temporal' (territorial) like that of nation states but also 'spiritual', based on the universal religious and moral 'mission of the Supreme Pontiff'. 67 As stated in art. 24 of the Lateran Treaty, 'in the international realm' this was a 'mission of peace', of mediation 'of temporal rivalries between […] States' through the 'exercis[e of the Holy See's] moral and spiritual power.' In the Lateran Pacts, Scott saw a practical step towards the return of the Pope to his customary position as the principal arbitrator of international disputes, one that would guarantee solutions on 'the basis of law, morality and the imponderables', 68 something he had been arguing for since the beginning of his career. Yet, this carving of a space for the legal recognition of spiritual power in international law was not a mere looking back to the past, but remained open and linked to technical and institutional advancements. Still, in 1939, Le Fur argued that the League of Nations had the potential of embodying the moral authority and mediating function in international affairs of the medieval Pope. 69

The politics of Neo-Scholastic international law
At a superficial glance, the endeavour of the Association International Vitoria-Suarez ended in failure. It had no shared achievement other than a collective book expounding 'the principles […] of the Spanish theologians of the Middle Age[,] recognized […] as the basis of modern international law'. 70 Born with ambitious plans of editions in several languages and contributions from a dozen internationally renowned luminaries, the book would instead be hastily put together by de La Brière as European politics quickly deteriorated. 71 Most copies of the book would remain in the basement of the publishing house Pedone for the duration of World War II. By the end of the conflict, Le Fur, de La Brière and James Brown Scott had died and their work would be soon largely forgotten. Verdross, instead, gained further prominence as a scholar and a practitioner, serving as a judge of the newly created European Court of Human Rights between the beginning of its operation in 1959 and 1976. His continuing reliance on the Scholastic tradition as he further developed his theory of international constitutionalism, in a post-war characterized by the return of Catholics to the centre of European politics, provides a strong link with the interwar developments outlined in this article. Also, the crucial intellectual and practical contribution of Catholics, including ultra-reactionary figures, 72 to the redesigning of the global order and European supranational arrangements is well documented. 73 Yet, the story of the interwar period as a laboratory for an intellectual synthesis of modern international law and Catholic universalism, through further exploration, could provide us sharper insight on post-war internationalism as a site of both renewal and restoration. The legacy of Vitoria and Suárez anchored these thinkers to the spiritual authority and tradition so crucial to the Catholic understanding of politics and community, but it also signalled their professional commitment to the interwar advancements of international law, a modern technical discipline despite its deep roots. By seeing beyond the commonplace Catholic prejudice against liberal internationalist solutions, they were able to conceive a modern international legal order in Catholic terms.
However, as the survey in this article suggests, the universal law they conceived was far from inclusive and ecumenical. Its function was to sustain a global order safe for Catholic values and the Church's spiritual authority. Its moral foundations were crystalized in vague driving principles such as einheit, bien commun, tradition or equality. In practice, though, these thinkers deployed these concepts consistently in militant terms. They recruited international law in a battle between good and evil, between the natural order of creation and the perverse ills of modern politics. And, if initially the enemy was identified in the full range of modern political doctrines, including liberalism and fascism, by the 1930s the focus was on communism and neutralizing popular sovereignty.
The document that articulated the Neo-Scholastic vision for international law most plainly was not destined for publication, but for the eyes of the Pope only. In 1935, as the volatility and polarization of European politics kept increasing and the risk of a new continental conflict loomed large, Pius XI, the pontiff who had presided over the Concordats with Fascist Italy and Nazi Germany, received a lengthy memorandum. Unoriginally, the text portrayed the world as going through a moral identity crisis. The solution lay in the recognition that international law was of Catholic origins. The authors of the memorandum walked the Pope through the original conception of the law of nations in the work of Augustine; its rationalization by Aquinas; its universalization by Vitoria and systematization by Suárez; up to its nineteenth century Thomist re-adaption by Luigi Taparelli d'Azeglio. Through their historical argument the authors sought to convince the Pope to issue an Encyclical claiming this 'Catholic conception of international law'. This would provide the world with the guidance needed 'to join once and for all morality and law in international relations by placing international law upon its true foundations[.]' The 'high standard of reason which, distinguishing between right and wrong, is immanent in the contributions of the Great Churchmen' could alone guarantee the 'orderly' and 'controlled growth' of the international legal order. 74 This direct marriage of Catholic teaching and international law did not find expression in an Encyclical, nor did the memo dwell on the precise nature of the 'inconsistent doctrines […] threaten[ing] civilization'. 75 The pedigree of the authors petitioning Pius XI, James Brown Scott and Edmund Walsh, helps us clarify its deeper intent. Scott consistently painted Vitoria as a prophet of liberalism and equality. 76 Yet, the liberalism he believed in was the elitist and paternalistic one of the US foreign policy establishment he rose to prominence in at the turn of the twentieth century. His idea of equality was the formal understanding that the courts of the Lochner era weaponized to strike down all legislation advancing the claims of the working class. The same formal understanding that allowed him to consider the US occupation of Cuba as the result of a just and selfless war. Indeed, in his reading of Vitoria, equality meant free trade and unimpeded capitalism to be legitimately imposed through just war, if resisted.
Le Fur or Verdross would have sneered at the notion of Aquinas and Vitoria being called liberals, as Scott put forward. Yet, their alliance with Scott embodies the slow opening of Catholic traditional anti-democratic stance to conservative forms of liberalism, finding common ground in the resistance to revolutionary politics and working class demands for structural change. Their shared interwar experiments provided a supranational legal framework conducive to that political project, engineering a world safe for Catholicism. Setting up a hierarchy of universal principles and a universal spiritual sovereignty for the papacy, they translated the idea that only a Catholic moral leadership could stabilize European and global politics into international legal doctrines.
The second author of the memorandum, Edmund Walsh, was a Jesuit priest and the founder of Georgetown University's School of Foreign Service that Scott taught in. If Scott dedicated himself to articulating the universal moral principles sustaining the Catholic conception of international law, Walsh focused on identifying and indicting its enemies. Walsh was a key expert for the Holy See on account of his experience of the Soviet regime as director of the Papal Famine Relief Mission to Russia in the years immediately following the Revolution. As such, he became a key figure in the Vatican's interwar anti-Bolshevik crusade that came to consume the earlier wider anti-totalitarian effort by the mid-thirties. 77 Walsh early on discounted the traditional Catholic narrative placing all modern political doctrines in the same basket and downplayed the idea of a genealogical connection between liberalism and communism. Communism for Walsh was qualitatively different, an incarnation of absolute evil. He made clear that opposing the Bolsheviks' 'militant political philosophy' with its 'claim […] to rule mankind in the mass' was not just a routine endeavour. It was the contemporary expression of 'an ancient conflict in which the protagonists are not men but principles'. 78

Concluding remarks: post-war legacies
The reunion of international law and Catholic universal morality engineered by the leaders of the Vitoria-Suarez Association produced an ideological toolbox that would prove successful. Alongside the other recent works on the Catholic interwar trajectory mentioned in the text, this article portrays how the rise of Christian Democracy and that of post-war Catholic internationalism, though somewhat unexpected and surprising to observers at the time, were not the result of a sudden, unpredictable change. Catholics did not have a democratic epiphany after World War II. The space for their new crucial role in secular politics was opened through a complex and ambivalent process of adaptation and appropriation, operating across a variety of discourses, both popular and academic. Understood in these terms, the Neo-Scholastic legal vision contributed to the eventual construction of the post-war 'constrained democracy' 79 in Western European states that Catholic political leaders would be at the forefront of. At the international level, it sustained the two key conceptual drivers of early European integration, human rights and functionalism.
The language of rights was familiar to both liberals and Catholics and could be couched in shared ways that would leave space for each's favourite key of interpretation, individualist and personalist, respectively. As enshrined in the 1950 European Convention, human rights embodied Verdross's vision of higher moral principles of international law, operating above state will. In the post-war phase, human rights served the main function of marking the supposed moral superiority and respect for human dignity of the Western regimes, as opposed to both left-wing internal opposition and the atheist and communist East.
Functionalist integration fit with the vision of European Catholic political leaders such as Robert Schuman for similar reasons. On one hand, its link to ideas of economic freedom and efficiency provided an ideal counter to the planned economies behind the Iron Curtain and their argued totalitarian nature. On the other, it offered a promising avenue to establish a pluralism of powers by establishing international institutions counterbalancing the dangers of absolute state sovereignty.
In their combination, human rights and functionalist integration forged a common platform to fight off the Soviet threat, convincing to pragmatic Catholics and conservative liberals alike. In simplistic terms, interwar Fortress Catholicism turned into the idea of Fortress Europe during the war and defence of the way of life outside the Iron Curtain after; broad-range anti-totalitarian thinking morphed into the virulent anti-communism of the early Cold War; the universal morality sustaining Neo-Scholastic international law inspired the rise of human rights discourse in the 1940s.
In more general terms, this article puts into focus the universalist aspirations of international law through its intimate relationship with religious discourse. This connection offers insight into the implications of the discipline's moral stance, too often obfuscated by narratives of progress and secularization. The universalist utopia of a single law of humankind drives emancipatory projects, genuinely claiming international law as a tool of inclusive justice. But the same moral charge also drives, paradoxically, international law's most exclusionary instincts by constructing morally charged black-and-white distinctions. Within this picture, it is clear that religious belief still plays a role in global governance and international legal arrangements. Learning from the more open discussions of the interwar years provides insight into current similar conceptual interactions, sidelining the thought-stopper of conceiving of law as a product of 'sanitized' technical thinking. International law is neither secular nor secularized. Accepting that promises a fuller understanding of the effects the universalist moral charge the discipline has on the realities of international politics, for better or worse. After all, we are again living in an era of resurgence of nationalism and crisis of the previously accepted universalism. International lawyers have already been losing faith in the secular for quite some time. 80 Notes