‘Peace throughout the oceans and seas of the world’: British maritime strategic thought and world order, 1892–1919*

Prior to 1914, British strategic thinkers considered the question of how to maintain British world power in the twentieth century. They developed visions of co-operation at sea between not only Britain and the Dominions, but also other states in the international system. During the First World War, these ideas merged with plans for the League of Nations, which British policymakers envisaged as a tool for enforcing peace through the use of sea power. This article explores these ideas, providing a different interpretation of the origins of the League, and the maritime strategic thought of key individuals including Halford Mackinder. designs for an international collective security by power.

In the late nineteenth and early twentieth centuries, British strategic thinkers -notably Sir Julian Stafford Corbett and Sir Halford John Mackinder -and policymakers developed designs for an international collective security organization, underpinned by sea power. These ideas evolved over time, especially during the First World War, ultimately culminating in the League of Nations project. The league envisaged, however, was different to the one ultimately established. The league imagined was intended to serve as a vehicle for the maintenance of British power, safeguarding the empire through international co-operation at sea between the member states. To these thinkers and policymakers, sea power remained the great strategic weapon of the day. As the American naval theorist Alfred Thayer Mahan put it, the sea was still 'the great means of communication between nations'. 1 Henry Spenser Wilkinson, the first Chichele Professor of Military History at the University of Oxford, claimed that the advent of the steam engine had increased the significance 'of sea carriage to the world more than ten-fold'. 2 The British maritime theorist Julian Corbett concluded that halting this seaborne trade through the use of blockade could 'destroy the national life afloat, and thereby check the vitality of that life ashore', making it 'the great deterrent, the most powerful check on war'. 3 An organized, internationalized form of this sea power would make this even more potent, reducing the likelihood of war through deterrence, while standing ready to defeat any recalcitrant states in the new world order. about the League of Nations, this article presents a different perspective on British strategic thought. One individual who sat at the nexus of ideas of Greater Britain and international co-operation at sea was Halford Mackinder, the famous British geographer. Mackinder is usually presented as a 'prophet' of land power who foretold British decline. 13 This article overturns the conventional narrative, presenting him instead as an advocate of sea power, who believed that international co-operation at sea would avert the fall of the British empire.
Co-operation with other powers had long been central to the so-called 'British way in warfare'. As the leading maritime power, Britain had the ability to secure itself against invasion, maintain its trade while stopping that of its enemies, and use its financial might to assemble and support coalitions on the European continent without needing to deploy a large army of its own. This was exemplified during the French Revolutionary and Napoleonic Wars, in which Britain had helped to assemble no fewer than seven coalitions in order to ultimately triumph over France. This was recognized at the time by General Sir Charles William Pasley, one of Britain's foremost military theorists of those wars. 14 It was a matter that also occupied British strategic thinkers almost a century later, in the face of arguments that Britain ought to retain its 'splendid isolation'. 15 Spenser Wilkinson was among those most engaged in this subject. He would go on to become a fellow of All Souls College, Oxford, and enjoy the support of Alfred Lord Milner, who even tried to find him a post as advisor to Prime Minister Herbert Henry Asquith. 16 He was also the brother-inlaw of Sir Eyre Crowe, one of the foreign office's most important diplomats. Wilkinson argued in 1896 that the opinion of the 'present day, that England shuns alliances, is in direct contradiction to the facts'. 17 He explained the historical dynamics of co-operation between Britain as a maritime power and its continental allies, stating: The conditions which obliged her to seek in the exertion of maritime power as the foundations of her own independence compelled her, at the same time, to associate her efforts with those of continental nations which, equally with herself, were seeking to ensure themselves against some dangerous preponderance. 18 Britain's geostrategic position meant that 'there has been a policy which has been so directed as to find allies'. Yet this was no sign of weakness; Britain had allies because 'she was strong and could help' continental states, whose independence Britain championed 'against the predominance of any one of their number'. 19 Beyond reminding Britons that an aversion to alliances was not a long-standing feature of British foreign policy, however, there was a more radical element to the discussion of the importance of allies to Britain in this period. Now British strategic thinkers began to discuss turning past practice in war into a peacetime policy to solve the problem of 'imperial defence'. Major General T. Bernard Collinson, a royal engineer, offered one The war policy that Pasley shadowed forth, can now be made a definite system. But the alliances that we should make are those of Asiatic powers as well as European, and thus the flanks along which our invisible force should move, are those of Asia and Africa, as well as Europe. 20 Collinson thought in global terms, beyond the mere European balance of power, anticipating the rise of states such as Japan. Alliances with maritime powers around the world would help to safeguard the British empire.
Wilkinson provided similar recommendations of his own. In 1892, in a work co-authored with the Liberal politician Charles Dilke, he wrote that alliances would be required if 'the unity of the Empire' in terms of defence could not be achieved. 21 Two years later, Wilkinson explained the mutually supporting relationship of British sea power and the European balance of power, stating that Britain's naval supremacy remained 'the outcome of a partnership between England on the one side and a combination of continental powers', all seeking to maintain 'the independence of states against some attempt at dominion'. 22 Wilkinson developed this understanding further in 1895, claiming Britain had little choice but to lead other states in war and peace in order to maintain its great power status. He also explored ideas for an international league of neutrals, which had been set out by Gustave de Molinari, a Belgian political economist. This conception envisaged these states -namely Belgium, Denmark, the Netherlands and Switzerlandworking together under British leadership to prevent the outbreak of war. They would provide as a deterrent 'a declaration of an intention to attack whichever party should be the aggressor'. Wilkinson recognized that there were numerous obstacles to creating an effective league of neutrals, but if these could be overcome, 'there would then be in Europe a power deciding questions of right or wrong between the European States, and enforcing its decision'. The league must be invested in the maintenance of the status quo, and British sea power would act as the arbiter in this system. However, Wilkinson was wary, reflecting that 'peace will have been secured, no doubt, but at the cost of putting humanity into a strait waistcoat'. Nevertheless, he believed that leading other states was critical to the future security of Britain, concluding 'that the geographical position of Great Britain is such that she is compelled either to lead mankind, or to lose, not merely her Empire, but her very independence'. 23 Wilkinson returned to this theme in The Nation's Awakening (1896). He now proposed a number of arrangements for a system of strategic alignments, spanning the globe, which synced with the ideas previously set out by Collinson. Britain would have a choice of strategic partners, including Austria, China, Germany, Italy and Japan. Defensive treaties could be negotiated with these states to safeguard mutual interests, involving 'action only when and in the case the specific interests were assailed'. He acknowledged that such a scheme -tantamount to a nascent collective security system -would prove controversial in some quarters. Yet he believed that international co-operation in peace would be necessary to sustain the British empire. This was the end, and given that public opinion 20  was in favour of this, the means were justifiable, whether they were 'naval, military, or political' -by which he referred to strategic alignments. 24 Wilkinson also countered suggestions that such alignments could be constructed upon the outbreak of war, arguing that this would leave Britain vulnerable to other states. It was too risky to depend on identifying states with mutual interests in the midst of a crisis. Yet as such national interests rarely are short-term, convergence between the interests of states must already exist independent of a crisis, so there was little sense in not seeking to make agreements with those states now. Furthermore, if Britain and its allies were capable of achieving the protection of those interests in war, Wilkinson believed that co-operation in peacetime might be equally as effective -'it is probable that their peaceful co-operation, regulated by treaty, would secure their objects, so long as they are defensive, without war'. 25 Wilkinson had thus begun to envisage the vague contours of a collective security system that would safeguard the British empire by avoiding war through defensive treaties.
On the other hand, if Britain did pool resources with other states in order to maintain peace, and opted for a course of isolation instead, Wilkinson explained that Britain 'must arm … to the point at which we shall have nothing to fear from any adversaries'. This required the construction of a significantly larger navy to defend Britain's global interests. In turn, alliances would be required to buy the time to create this force -and therefore neglecting international co-operation was not a sensible course either way. Consequently, Wilkinson concluded that it was vital that Britain 'create a world-wide system of defence' with other states, in their mutual interest and defence. If Britain opted against this course, it would appear 'a decayed nation' in international relations, accelerating its decline. If Britain would not take up the mantle of leadership, other states would seek to prey upon its weakness, calculating 'how they can best acquire a share in the spoil'. Ultimately, co-operating with and leading other states signified the enduring strength of Britain, rather than its weakness. 26 While Collinson and Wilkinson explored ideas for co-operation with other powers, theirs was not the only vision for the maintenance of British power in the twentieth century. While Alexis de Tocqueville had famously predicted the emergence of Russia and the U.S.A. as superior great powers in the coming years, other visions imagined a different future -albeit one in which power was nevertheless concentrated among a handful of political entities. Race, according to Duncan Bell, was viewed as 'the basic ontological category of politics' in this period. 27 Consequently, visions were developed of future pan-Latin, pan-Teutonic and pan-Slavic empires that would unite states and enhance their power in the international system. British thinkers believed that, alongside these, a polity of the 'English-speaking peoples' would form, based on the existing British empire. This grouping would prove stronger than its new rivals, shatter the old European balance of power and maintain peace around the world. 28 In turn, it would 'assume the responsibility of global leadership'. 29 The key to forming this new polity, however, was to 24  turn Great Britain into Greater Britain. The British empire would need to be reorganized via imperial federation so that Britain and its Dominions -Australia, Canada, New Zealand, Newfoundland and South Africa -were more closely integrated in terms of trade, governance and defence. This would be the 'agent for securing global power and prestige'. 30 The issue of 'tariff reform' championed by Joseph Chamberlain remains the bestknown aspect of this project. Creating external barriers to trade would enhance economic interdependence within the empire, helping to ensure its cohesion. Governance, however, was at the core of the thinking of members of the 'Round Table'. This was a group of influential academics and politicians, including the likes of Lord Robert Cecil and Philip Kerr. This was centred on the nexus of the University of Oxford. The Round Table sought to bring 'imperial federation' to reality, imagining an imperial parliament sitting in Westminster. These hopes rested on the belief that new technology, notably the steam engine and telegraphy, would reduce the significance of geographical distance, bringing Britain and its far-flung empire closer together. 31 William Forster, a Liberal politician, argued that these innovations made it now 'possible for a nation to have oceans roll between its provinces'. 32 Greater Britain was viewed not merely as an opportunity, but a necessity -once again the spectre of imperial decline loomed large. As with Collinson's and Wilkinson's analyses, at the core of the Greater Britain project was the belief that Britain alone would not be capable of maintaining the empire and its position in international relationsco-operation, of a sort, would be required. The Dominions were not sovereign states, however, differentiating these visions from the genuinely international co-operation explored by those thinkers. Yet they were viewed by a number of British leaders as, at minimum, quasi-independent states who could soon reach that stage -the only aspect of their governance that remained in London's hands was foreign policy. Consequently, the rhetoric of 'children' coming of age to assist Britain was frequently employed in the late Victorian and Edwardian era. In 1902 Chamberlain infamously proclaimed that 'the weary titan staggers beneath the too vast orb of its fate. We have borne the burden for many years. We think that it is time that our children should assist us to support it'. 33 Arthur Balfour, during his tenure as prime minister, stated that 'those who were our children are gradually becoming our equals … as they grow up, [they] shall aid their parents'. 34 This matter also interested British maritime strategic thinkers. John Colomb reflected that the Dominions had progressed from 'struggling communities … to great free states' over the previous century. 35 Julian Corbett, a fellow maritime theorist, held similar views. In 1900 he published an article titled 'The paradox of imperialism'. He contended that 'the progress of civilised society has always been from the smaller to the larger political  unit', implying that a new relationship between Britain and the Dominions was a logical next step. He entwined this with 'liberal' political philosophy, arguing 'that the very fact of forming a large group connotes increased liberty in the parts' producing 'a tendency towards democracy', seeking to deflect criticisms concerning the over-concentration of power at the imperial centre. He concluded that 'the conception of the British Empire is that of a commonwealth of States under the hegemony of the oldest and most powerful of them', and it was vital to Britain's future that, rather than drift apart, these states remain bonded together. 36 Sea power remained critical to the maintenance and defence of the empire -and a unifying element of Greater Britain. Mahan wrote that Greater Britain 'in action, will manifest itself pre-eminently along ocean and naval lines'. 37 Yet there remained an unanswered question of tremendous significance in debates over Greater Britain -what role might the United States play? The project was founded on ideas about the unity of the 'English-speaking peoples', so there must therefore be a role for the 'lost Dominion' of America. This, along with ideas of the Dominions emerging as 'free states', meant that the project was perhaps less distant from the conceptions of Collinson and Wilkinson than might be imagined. Indeed, much as Wilkinson emphasized shared interests, proponents of Greater Britain recognized that ideas of race alone would not suffice, and the Americans would need to be engaged on the grounds of mutual interests. It was in this vein that Sir Arthur Balfour, then first lord of the treasury, told Mahan that American and British interests 'are identical… We have the same interests in peace'. 38 Security and the maintenance of peace would be at the centre of any future Anglo-American agreement -as would sea power. Alfred Lord Milner, who was at the fore of the Greater Britain movement, not least because many of his acolytes dominated the Round Table, told an audience at Harlesden in 1885 that Britain must create a 'great Anglo-Saxon Confederation', to be 'firmly united for purposes of mutual protection'this would provide 'the best security for universal peace'. 39 In a similar vein, Rear Admiral Sir Charles Beresford, one of the Royal Navy's dominant personalities in this period, authored an article envisaging an Anglo-American entente. Sea power was explicitly at the core of his conception -the 'heavy sword' that Britain and the U.S.A. would wield together as arbiters in the international system. 40 Sir George Sydenham Clarke, who would become the first secretary of the committee of imperial defence, meanwhile offered his own conception for an Anglo-American union. He was wary of mere ententes or alliances, so pressed for a more formal political arrangement -a 'naval union' between Britain and the U.S. This would be 'a real federation' upholding 'abiding peace throughout the oceans and seas of the world'. He claimed that their 'instincts and aptitudes [were] derived from a common ancestry' -yet interests mattered too. Economic interdependence meant that both states were invested in protecting 'the ocean routes of the world'. This concern would prove unchanging, enabling the creation of a permanent relationship that transcended the transient alliances of Europe. Moreover, Clarke -like Mahan -recognized that the U.S.A.'s relative position was considerably weaker than Britain's, so co-operation at sea would be a sensible first step towards the U. into a great power. He concluded that 'no other policy could open out to the American Navy such a noble prospect of world-wide beneficence'. Ultimately, a 'union of the two nations in a naval league could in truth dictate, at will, peace throughout the sea highways of the world'. The British empire's naval bases could assist the United States Navy, while 'the Navy Department and the Admiralty would be brought into close communication', with new arrangements created for sharing intelligence. 41 Similar ideas and plans were propounded elsewhere. 42 There was even Anglo-American collaboration on the subject -Beresford and Mahan published a piece in the North American Review in which they discussed 'Possibilities of an Anglo-American reunion'. 43 However, it was not until 1904 that a British intellectual began to tie these strands -of Greater Britain, an Anglo-American reunion and wider international co-operation -into a singular, cohesive vision.
Halford John Mackinder was a British academic who was appointed as the first reader in geography at the University of Oxford in 1887. This provided him with a platform to advance the study of geography as an academic discipline, and it also brought him into contact with Lord Milner. He and Leo Amery, another fellow of All Souls, decided to tempt him away from academia. They paid him -via the Rhodes Trust -to dedicate his attention to these questions, and before long Mackinder transitioned into a political career, ultimately winning a seat in parliament in 1910. 44 Mackinder had come to their attention due to his writings on imperial federation and defence, including his 1902 book Britain and the British Seas. 45 Yet Mackinder's contribution to this debate, and his strategic thought more broadly, has been misunderstood in much of the historiography.
The conventional image of Mackinder and his strategic thought rests on ideas he set out two years later, in an address to the Royal Geographical Society, later published as an article titled 'The geographical pivot of history'. In this article Mackinder appeared to forecast the end of the so-called 'Columbian epoch' in which European states had dominated the world through sea power in the fashion described by Mahan in The Influence of Sea Power Upon History (1890). Mackinder seemingly argued that the utility of navies and shipping would decline in the twentieth century, overtaken by technological advances on land, notably the expansion of transcontinental railway networks. Mackinder claimed that these developments would benefit continental land powers -namely Germany and Russia -who would be able to exploit this enhanced strategic mobility with their armies to dominate the continents of Euro-Asia and Africa. From there they could exploit the resources of these continents to develop their power, overawing maritime states like Britain, enabling them to establish 'the empire of the world'. 46 Mackinder's intention and argument has been misunderstood by a number of observers, both at the time and since, but has nevertheless become a cornerstone of the study of geopolitics, and a key reference point for works on sea power in the era of the First World War. In the same week that he delivered the paper at the Royal Geographical Society, the 41  The most influential work on Mackinder in the history of strategy and war has been authored by Paul Kennedy, first in a journal article published in 1974 titled 'Mahan versus Mackinder: two interpretations of British sea power', and also in a chapter in his book Strategy and Diplomacy, published in 1983. Kennedy's argument, as the name suggests, was that Mahan and Mackinder were diametrically opposed. Mahan's credentials as a prophet were challenged, with Mackinder portrayed as the more prescient of the two thinkers -or 'the better prophet'. Central to Kennedy's argument was his claim that Mackinder believed that 'sea power itself was waning in relation to land power', with the great strategic weapon of blockade losing its effectiveness. Kennedy then explained how this clash of perspectives played out in the first half of the twentieth century, with Mackinder proven right. Britain declined, and 'sea power appeared to be a subsidiary factor' in the First World War, while the Second World War confirmed 'those trends which Mackinder had detected at the turn of the century'. 50 Given Kennedy's reputation as an authority on British naval history, burnished by the publication of The Rise and Fall of British Naval Mastery (1976), few historians or scholars of international relations challenged this view. Instead, Mackinder has remained a staple in the classics of strategy as an alternative to the caricature of Mahan's theories emphasizing the importance of naval battle. Even Mackinder's most important biographer, Brian Blouet, presented this perspective of Mackinder. 51 More recently, Andrew Lambert has argued that Mackinder 'attempted to frighten [Britain] to change its culture from seapower to continental empire'. 52 Lambert is correct to argue that Mackinder's lecture aimed to shock -but it was not his aim to turn Britain into a continental empire. Instead, he sought to spur British transformation in a different direction to counter the emerging threat from 'Euro-Asia'. He did not believe that Britain could become a land power -Britain would remain a maritime power, and it had little choice as it could not shift its geostrategic position. 53 However, it needed to enhance its co-operation, within the empire and internationally, to bolster sea power and safeguard the British empire. Indeed, sea power would retain its utility in the twentieth century if this could be achieved. 54 An exploration of Mackinder's broader thinking in the years prior to 1914 helps to reveal this. In Britain and the British Seas Mackinder stressed the 'freedom in the selection of that point at which to deliver an attack with land forces' that navies offered, underlining 'the consequent mobility of sea power'. 55 Unlike railways, which were rooted to the ground, deployment from the sea offered an element of surprise and flexibility that could not be matched. Indeed, the limitations to railways was often discussed by British maritime theorists and policymakers -after Mackinder's lecture at the Royal Geographical Society, the Conservative politician Leo Amery contended that 'fifteen or twenty parallel lines of railway' were required to match the capacity of seaborne transport. 56 Corbett, a lecturer at the Royal Naval College, echoed these views in 1907, arguing that claims that railway networks could match maritime communications 'ignore universal experience and the elementary facts of commerce'. 57 Britain and the British Seas concluded with a discussion of the future of sea power. Here Mackinder set out his vision of Greater Britain. He discussed how the British empire was 'ultimately held by naval power'. Yet this meant that there was no guarantee of permanence or prosperity, and 'grown poorer, Britain may no longer have the means of building and maintaining an adequate fleet, and may lose command of the sea. Other empires have had their day, and so may that of Britain'. The key was to adapt to the 'new balance of power [that] is being evolved'. The expansion of the power of Germany, Russia and the United States meant that 'Britain could not again become mistress of the seas. Much depends on the maintenance of a lead won under earlier conditions'. All of the British Dominions were threatened by this, however, and this 'may prove to be the most effective cement of the incipient British Federation' -or Greater Britain. The Dominions would soon 'be ready to share in the support of the common fleet, as being the cheapest method of ensuring peace and freedom to each'. 58  such time as the daughter nations shall have grown to maturity, and the British Navy shall have expanded into the Navy of the Britains. 59 Mackinder's famous 1904 lecture built directly on this lesser known work, but approached it from the reverse angle. He did not dwell specifically on the utility of sea poweralthough he did reference the importance of the works of Mahan. As noted above, his aim was to shock the Edwardian elites -policymakers and academics -into action.
Mackinder's lecture provocatively outlined the possibilities open to states such as Russia or Germany, and this aspect of the lecture remains the best remembered. However, what was perhaps even more significant than the problem was the solution he offered -a matter that has received limited attention from scholars. A closer reading of this article reveals a different interpretation, of Mackinder explaining how maritime states could counteract the growing advantages of land powers like Germany and Russia by working more closely together. Here Mackinder developed his ideas beyond the confines of Greater Britain, a point often overlooked. 60 He later reflected that, when he wrote the article, the Russo-Japanese War (1904-5) 'was looming before us and my mind was struck by the context between the exertion of British sea power over 6000 miles to the cape and that of the Russian landpowere [sic] over 4000 miles of the newly completed transsiberian line'. 61 Mackinder recognized that, as an insular power, Japan faced a similar threat to Britain and its Dominions. The answer lay in co-operation at sea between these states, counterbalancing the land powers on the Eurasian continent. In this, Mackinder was similarly influenced by other on-going events. In 1902 the British government had negotiated a formal alliance with Japan (albeit not one that demanded British intervention in 1904). The year Mackinder gave the lecture, Anglo-French relations thawed to the extent that the Entente Cordiale was agreed -not an alliance, but a first step towards a strategic alignment.
In his lecture Mackinder explained that 'Britain, Canada, the United States, South Africa, Australia, and Japan are now a ring of outer and insular bases for sea-power and commerce, inaccessible to the land power of Euro-Asia'. Like Collinson and Wilkinson, Mackinder believed that a system of global strategic alignments with these states would bolster British security. This alignment would consist primarily of the 'outer crescent, Britain, South Africa, Australia, the United States, Canada, and Japan', which encircled the Eurasian and African continents. The U.S.A. was crucial, as it 'has recently become an eastern power, affecting the European balance not directly, but through Russia'. France would similarly provide 'an equipoise' versus Russia in Europe. This could be extended to 'Italy, Egypt, India, and Corea [sic]' in supporting Greater Britain, creating 'so many bridge heads where the outside navies would support armies to compel the pivot alliances [such as Germany and Russia] to deploy land forces and prevent them from concentrating their whole strength on fleets' and overpowering the maritime states at sea. Lastly, South America would have a critical role to play, potentially 'strengthen[ing] the United States'. Mackinder concluded that this system of strategic alignments, founded on the 'outer crescent', would be capable of counterbalancing the pivot states, which would have 'limited mobility as compared with the surrounding marginal and 59 Mackinder, British Seas, p. 358. 60 One brief but notable exception to this is the discussion in Pelizza, 'Geopolitics, education, and empire', p. 120. 61 Bodl. Libr., MS. School of Geography, C/300, Box 88, H. Mackinder, 'The round world and the winning of the peace', draft article, n.d. insular powers'. 62 Mackinder's message was clear: the enhanced mobility of land powers effected by railways could be overturned by increasing co-operation at sea between the insular powers.
Mackinder's analysis of the 'outer crescent' was no after-thought, but the key part of the lecture. Leo Amery emphasized the line about 'bridge heads' in his personal copy, and later made a similar argument in a piece on geopolitics, suggesting that -as with Japan -France represented 'an invaluable ally'. 63 Amery also contributed to the discussion after the lecture -often ignored in summaries of Mackinder's argument -and in his reply Mackinder elaborated further, shedding additional light on his continued faith in sea power, and co-operating with the 'marginal states' such as France and Italy: I quite agree that the function of Britain and of Japan is to act upon the marginal region, maintaining the balance of power there as against expansive internal forces. I believe that the future of the world depends on this balance of power … We must maintain our position there, and then, whatever happens, we are fairly secure. 64 Mackinder and Amery knew each other well, and they were both members of the Coefficients, an Edwardian dining club, along with the likes of Lord Robert Cecil, Sir Edward Grey, Richard Haldane, Alfred Lord Milner and H. G. Wells. The Coefficients discussed matters such as imperial defence and the future of the British empire, producing minutes to accompany their discussions. In March 1905 the question of sea power arose. Amery and Mackinder authored the minutes, concluding that blockade was capable of ruining Germany or the United States, while sea power could produce strategic results on land through the development of alliances. 65 Mackinder expanded on these themes in his subsequent works in this period, explaining how sea power remained a potent tool in both war and peace, enabling Britain to draw other states into friendly relations or strategic alignments. In the National Review he contended that 'a league with [the U.S.A.] on terms of equal alliance is an attractive ideal, but the condition is strength on our side no less than the other'. He continued: At Fashoda we prevented a French command of Africa, but it must not be forgotten that the seapower which then won without challenge is also the basis of our friendly compact with France… The present value to Japan of the British alliance is the guarantee afforded by the British fleet. In other words, power is essential no less for international friendships than for conflict, and in both ways adequate power makes for peace. 66 The following year, Mackinder reflected that 'not once in these twelve years has the British fleet been engaged in battle, yet it has helped to win for us the friendship of America, of Japan, and of France'. 67 J. Ellis Barker made a similar point in 1910, concluding that 'foreign nations conclude alliances not with the British nation but with the British Fleet'. 68 British sea power, then, won allies without needing to resort to war. This peacetime dynamic helped to secure the British empire, reducing the number of threats facing it, while garnering support internationally. In turn, the assistance of the Royal Navy could provide Britain with more manpower. As Mackinder put it, Britain might 'economise [its] manpower by alliances', remedying its lack of a large standing army. 69 Mackinder also identified other benefits for Britain beyond defence, such as the preservation of British access to the Chinese market via the alliance with Japan.
Ultimately, the events that Mackinder lived through appeared to confirm the continued importance of sea power in international relations. Following the Agadir Crisis in 1911, in which Germany threatened France over Morocco, Mackinder added it to his list of 'distinct occasions when by using our Fleet, by throwing it into the balance, we have achieved silently the consequences of a great naval victory'. In addition to Fashoda among others, during the Agadir Crisis, 'when Germany suffered her silent defeat … we won a victory for our ally; we maintained peace in Europe and the balance of power'. While he framed the 'geographical pivot' as an opportunity for continental powers, the reality on the eve of the First World War was that 'Germany cannot appear anywhere in the world without running the gauntlet of our Fleet'. 70 In response to the Agadir Crisis, Britain and France also negotiated a naval agreement over the course of 1912-13, with the French taking on responsibility for the Mediterranean while Britain focused on the North Sea in the event of a war in which the two states were allies. 71 In the midst of this, senior foreign office officials were also pondering the wisdom of entering into more formal agreements, increasingly worried 'that some day we shall be left alone', 72 even 'stranded in splendid isolation'. 73 Elsewhere, the most successful element of the Greater Britain project was proving to be that which concerned sea power, with the Royal Canadian Navy founded in 1910, while the Royal Australian Navy followed a year later. Mackinder reflected that the Dominions have organised forces for their own defence, and for the assistance of the Empire in time of need … It is recognised throughout the Empire that we can maintain our independence, keep up the communications between our various territories, and bring the strength of the whole to bear for the defence and support of each of its parts. 74 Spenser Wilkinson was similarly pleased, calling them 'the true schools of British nationalism, which require only time to realise all the unity that we have ever dreamed of '. 75 It appeared, then, that British policy was moving in the direction hoped for by British strategic thinkers. However, to bring about the radical developments they discussed required an event that would upend the existing world order.
Although the links between British strategic thought and policy towards international co-operation at sea prior to 1914 are challenging to pinpoint, the evolution of British policy towards the League of Nations was much more neatly tied to British strategic thinkers, with intellectuals playing an important role in British departments of state, notably the foreign office. 76 Yet the important strand of thought developed by liberal 69  imperialists, comprising the likes of the Round Table, has received considerably less attention in the historiography than the liberal internationalists of the Bryce Group. Meanwhile the views of thinkers such as Corbett and Mackinder have been neglected or misunderstood. Yet these thinkers were heavily involved in the debate over the creation of a post-war league. From an early stage the Round Table made their views known to key policymakers such as Sir Edward Grey, and he 'spoke really very warmly of the work' they were carrying out. 77 Their connections to the cabinet were enhanced in 1916, after Philip Kerr became an advisor to the prime minister and Lord Robert Cecil was appointed minister of blockade, while Corbett himself became enmeshed in Whitehall. The final part of this article will briefly explore how British designs for a League of Nations evolved in the visions of these strategic thinkers. The core tenets of pre-war ideas for a system of strategic alignments underpinned by sea power -centring on Greater Britain but expanding to the United States and beyond -remained a crucial aspect of these conceptions, fusing with the wider league project. 78 In August 1914 Britain joined France and Russia, along with a host of smaller powers, in a struggle against Germany and Austria-Hungary. Although Britain would develop its land power, raising a large army to deploy on the Western Front, this was viewed by many British elites as a wartime expedient. In turn, a large standing army did not feature in many British visions of the post-war world. However, a new means for guaranteeing security and reducing the prospect of war was needed. H. G. Wells -a former member of the Coefficients -famously wrote of The War That Will End War in 1914. While it is remembered as a utopian assessment that the Great War would end all wars, a closer examination offers a different view. Wells sketched a plan for a postwar strategic alignment, called 'the Confederated Peace Powers', which would maintain peace. Their navies would enforce 'the neutralisation of the sea', halting armed ships of other states using it. They would also wield blockade against any recalcitrant states. Wells was confident that blockade would produce the defeat of Germany in 1915 and was therefore critical to securing the post-war order. As he concluded, 'Those who know best the significance of the sea power will realise best the reduction in the danger of extensive wars on land. This is no dream. This is the plain common sense of the present opportunity'. 79 Before long, British policymakers were actively discussing this 'opportunity'. Inspired by the Bryce Group's pamphlet, Richard Haldane -another Coefficient who now occupied the post of lord chancellor -was the first minister to bring the matter to the cabinet. Like Mackinder, Haldane warned that Britain's position might be imperilled if it did not act, 'otherwise great changes may take place in the organisation of seapower'. The solution was to make 'a definite agreement, to which not only the Allies but the other Great Powers will have to be parties, to take such steps as will make it perilous for any Great Power to develop unduly the means of aggressive action'. This would involve using 'sanctions' -notably 'economic pressure', presumably exerted at sea -to ensure 'the preservation of the peace of the world'. The following month, Asquith was forced to bring the Conservatives into a coalition government, leading to the addition of new members to the cabinet who were sympathetic to these ideas. Balfour replaced Winston Churchill as first sea lord. Having been a key part of the government that negotiated the Anglo-Japanese alliance and overseen its renewal while prime minister in 1905, Balfour had long been interested in strategic alignments. In 1916 he turned his attention to the possibility of an Anglo-American alliance as the core of the post-war order, mirroring earlier proposals by Charles Beresford and George Clarke. He argued that 'any effective sanction to preserve peace and the free development of nationalities "must consist largely in the potential use of seapower"', so the U.S.A. and Britain 'ought not to renounce the sea-power they possess, but … to organise it "in the interests of an ideal common to the two States"'. 81 These views were closely aligned with the view of the Round Table, as expressed in articles authored by the editor of its journal, Philip Kerr. He had privately told other members that 'if the Round Table is to maintain its influence it must have a policy in international affairs, no less than in Imperial affairs', therefore 'the policy of the British Empire should be directed constructively towards the formation of a Concert of Nations'. 82 He urged them to 'work out … the principles of an international system which will give peace and security to the Empire and to all other states'. 83 Greater Britain and the League of Nations project now entwined, much as Mackinder had proposed in 1904. In a series of articles published in the journal, Kerr expanded on this vision. He argued that 'sea power is and must be the chief sanction behind international liberty and right'. 84 Britain must therefore play 'the leading part in ending war', and 'in co-operation with other peoples, to endeavour to create a true reign of law over all the earth'. 85 In December 1916 Asquith's position had become untenable, and he was replaced by David Lloyd George as prime minister. This prompted further shifts, a number of which elevated those who had begun developing conceptions of post-war international co-operation at sea to enforce peace. Lloyd George assembled a 'War Cabinet' to direct Britain's war effort, which included Lord Curzon and Alfred Lord Milner. Sir Maurice Hankey was to be the secretary of this War Cabinet, and Milner used his influence to have Leo Amery appointed as assistant secretary. 86 Also working closely with Hankey during the war was Julian Corbett. His work for the navy prior to the war had continued, writing public pamphlets and advising on naval affairs. Yet as the war progressed, his talents were directed towards British strategy more broadly, working for the committee of imperial defence on matters such as assessing the attrition of the German field army. 87 He even composed cabinet memoranda, 'shaping the intellectual core of an evolving British war state'. 88 Kerr, as noted above, became a key advisor to Lloyd George. Lord Milner expected 'that Kerr would have "a great chance at making himself heard"' -and he eventually was seen as 'the "power behind the throne"'. 89 Balfour meanwhile moved to one of the great offices of state as foreign secretary. Within a matter of months, he was despatched to the U.S.A. following President Wilson's decision to take his country into the war. In the existing literature the Balfour mission is framed as being exclusively focused on working out arrangements for how the U.S.A. could best contribute to the Allied war effort. 90 Elsewhere, historians such as Peter Yearwood claim that Balfour's 'enthusiasm for the league was barely perceptible', and during his mission to the U.S.A. 'he hardly mentioned the league'. 91 However, an important aspect of the mission -albeit one widely overlooked -was how to bring the U.S.A. into Britain's plans for post-war order. 92 While Balfour was in the U.S.A., the imperial war cabinet decided that 'the existence of our own dominating sea-power, coupled with the seapower of America, was undoubtedly the best guarantee for peace'. 93 This subject was on Balfour's mind too. During his trip American policymakers expressed their reluctance to direct shipyards to produce the destroyers and light craft necessary for anti-submarine warfare, as this would mean halting the construction of battleships. To ensure that this was not detrimental to American maritime security, Colonel Edward Mandell House -President Wilson's close confidant -suggested that Britain should 'give us an option on some of her major ships in the event of trouble' after the war. 94 Balfour recognized that this opened the door to forging a post-war strategic alignment with the U.S.A., which would serve as the core of a League of Nations. Balfour reported to London that 'there would be a great advantage in obtaining anything in the nature of a defensive alliance with the United States'. 95 Lord Robert Cecil replied that the 'War Cabinet … are in general agreement' and wished to offer 'a formal guarantee of naval aid to the U.S. for the future and out of that to develop a definite naval alliance'. 96 Balfour returned to London himself and began developing plans for a post-war naval alliance, and presented it to the war cabinet on 19 June 1917. 97 Balfour aimed to bring not only the U.S.A. into a strategic alignment with Britain, but also its long-standing ally Japan and its wartime coalition partners France, Italy and Russia. They would 'engage singly and severally to assist each other against any maritime attack for a period of four years after the conclusion of the present war'. 98 This would be a maritime collective security system, and with the exception of the inclusion of Russia -still a member of the Allies at this time -it bore a striking resemblance to the alignment of 'insular powers' envisioned by Mackinder in 1904. Balfour stated that 'there is nothing I should like more than a defensive Alliance with America, even for four years, as would be capable of extension and development'. Bringing Japan into this agreement would then safeguard the British empire and maintain 'stability in international relations in the Far East'. As with Mackinder's 'crescent', Balfour saw France and Italy as logical partners in this maritime system, but was warier of Russia, arguing that its 'geographical position would prevent her navy taking any important part in the struggle'. 99 The cabinet mandated Balfour to commence negotiations with the U.S.A. on this issue, and Balfour wrote to House with his plan on 5 July, informing him that 'the Cabinet were and are profoundly attracted by the idea of a defensive arrangement with the United States'. Moreover, he explained that this should not simply be confined to the U.S.A., but should also involve the other Allied powers. In turn, he told House, 'it would seem to afford, besides every thing else, a foundation for a maritime league to ensure the peace of the world'. 100 House was in favour of at least an Anglo-American agreement, and noted in his diary that Balfour's suggestion was 'of such moment, and of such a delicate nature that the greatest care needs to be taken'. 101 Yet he had not kept the president updated on these developments, and it proved too difficult to secure his support for such an ambitious plan at this stage. In a meeting with Sir William Wiseman, a liaison between the White House and the British government, Wilson declared that 'while the U.S. was now ready to take her place as a world-power', it would not 'commit herself to any alliance with any foreign power' -at least not before the end of the warmuch to House's disappointment. 102 Balfour's plan would have to wait.
In the meantime, Mackinder himself continued to develop his own conceptions of the future of world order, and they continued to chime with Balfour's. In August 1916 he had declared that a unified British empire, joined by the U.S.A., must act as the bulwark 'of Freedom and Democracy in the world at large'. 103 He also remained convinced of the importance of maintaining Britain's European allies after the war. In 1917 he proclaimed that they must establish a common 'Institution' to ensure continued political and economic collaboration. He described how 'Britain, Italy, and France had become "sisters" living in the same house', protecting the maritime world from the central powers. This should be turned 'into a vast "defensive unit" from Scotland to Sicily' to give 'a long lasting "roman peace" to all the peoples of Europe'. 104 Also in 1917 Julian Corbett began to write about the formation of a post-war league for a public audience. He was commissioned by the foreign office to write a pamphlet on the issue, titled The League of Peace and a Free Sea. While primarily intended to unofficially set out Britain's view on the 'freedom of the seas' -a question proving difficult with the White House -it also revealed British thinking on the league project as being centred on international co-operation at sea. Although Corbett had briefly engaged with the question of international organization in 1900, he now emerged as one of Britain's foremost thinkers on this matter. This has been neglected in the existing literature, other than a brief but notable mention by Andrew Lambert. 105 Corbett argued that the postwar league must be able to wield sea power, using it as 'a sanction of international force', but the American definition of freedom of the seas would hinder the ability of the Royal Navy and U.S. Navy to do this.
In the same year Corbett delivered a lecture that built directly on his vision in 'The paradox of imperialism' for the future of the British empire. It must become a 'sea commonwealth'. 106 His conception here remained restricted to Greater Britain, explaining how sea power should be devolved to the Dominions (and possibly India too), creating 'separate centres of foreign policy'. Essentially, the British empire would become a collective security system of independent states linked by the sea and their sea power in a network of strategic alignments. This was to be the 'League of British Nations', in which 'the old bond of union reasserts itself more strongly than ever'. Together, they would possess sea power 'produced by a united effort of the whole organism … in joint labour and sacrifice is ever found the surest bond of union'. While Corbett focused on Greater Britain in this lecture, it was clear that enabling the Dominions to become independent states would open the way to other states joining this collective security system. Indeed, Corbett argued that this league would 'make for the peace of the world and comity of universal intercourse', guaranteeing free trade and preserving peace for all states. 107 Leo Amery pondered these ideas in the autumn of 1917, writing in his diary that -while Greater Britain remained his primary objective -he believed that international co-operation at sea might serve 'as the foundation of a wider synthesis in the future, i.e. the real ultimate League of Nations'. 108 Although there was no end to the war yet in sight, in early 1918 it was clear more concrete action was required on the League of Nations project. By now, Britain, France and the U.S.A. had publicly committed to a post-war league of some description. Balfour and Cecil therefore decided to create a committee to define the details of British plans for a league, to be chaired by Sir Walter Phillimore. The Phillimore committee brought together three eminent British historians: Corbett, John Holland Rose and Albert Frederick Pollard (the former two notably being naval historians, with Rose shortly to be appointed the first Vere Harmsworth Professor of Imperial and Naval History at the University of Cambridge). They were joined by three senior members of the foreign office: Sir Eyre Crowe, Sir William Tyrrell and Sir Cecil Hurst. Bringing together academics and diplomats to produce reports for senior policymakers in the foreign office was merely the formalization of social links that had seen these groups in conversation over the issues of sea power and world order for decades. Now these representatives attempted to start shaping the post-war world order.
While the reports produced by the Phillimore committee were co-authored, another pamphlet by Corbett in 1918, titled The League of Nations and Freedom of the Seas, provides a clear window into his thinking in the final year of the war. Once again he warned against the American definition of freedom of the seas -likely because President Wilson had made it the second of his Fourteen Points for a post-war settlement -warning that it would mean that the League 'cannot be an effective instrument for peace'. Sea power was 'at once the most readily applied and the most immediate and humane' sanction that the League could wield. Moreover, 'the force of an ecumenical sea interdict has become perhaps the most potent of all sanctions', and international co-operation at sea would bolster this sanction. Indeed, Corbett envisaged Britain and the U.S.A. -'the most weighty and convinced advocates of a League of Nations' -being at the core of this organization, for 'without their cordial support such a League can never be formed'. 109 In March 1918 the Phillimore committee produced its first report for Balfour. They had examined an array of ideas for a league, and determined that Britain ought to form a collective security system with other states at the conclusion of the war. It must possess the sanction of sea power -'the Allied States shall detain any ship or goods belonging to any of the subjects of the covenant-breaking State, or coming from or destined for any person residing in the territory of such a State' -and would use this economic pressure to enforce peace. 110 This report pleased the foreign office, regarding it as a blueprint for British policy towards a league. 111 Cecil proposed 'that the Phillimore Report should be immediately circulated to the Dominions Representatives', aware that the league would also see the realization of Greater Britain, as Kerr had explained to the Round Table in the early years of the war. Thereafter, Cecil told the prime minister, the imperial war cabinet may 'express a general approval of the lines on which it proceeds, as furnishing a hopeful basis for discussions and negotiations with our Allies'. 112 The Phillimore committee issued its final report on 3 July 1918, confirming its initial conclusions. It provided a more comprehensive analysis of the ideas of British intellectuals for a league -notably from the members of the Bryce Group -but special attention was paid to the ideas of Henry Noel Brailsford, a journalist. In 1917 Brailsford had published a book titled A League of Nations, in which he emphasized sea power as being critical to the project, for 'without it such a League would be almost unthinkable'. He then explained how this could function, noting that the league might need to resort to the 'extreme exercise of sea-power' in terms of blockading the enemy. In turn, he argued that 'our naval supremacy is the key to the future of the League -nay, to the future of civilisation'. 113 These ideas were of considerable interest to the Phillimore committee, which seized on the idea that the 'the extremer uses of sea-power shall be reserved for wars declared or sanctioned by the League', providing a footnote stating, 'This is an ingenious suggestion, and worthy of consideration'. The report reflected that Brailsford 'would use sea-power as a weapon for States carrying out the common interest'. 114 Although it has received limited attention in conventional narratives of the creation of the League of Nations, the Phillimore committee's scheme proved to be a critical document in the British approach to the project in 1919. Not only did it convey the views of academic and diplomats to politicians, but it suggested that Britain should take a leading role in the creation of an international collective security system underpinned by sea power. This was the culmination of decades of developments in British maritime strategic thought and ideas of world order.
Although Mackinder's ideas aligned with thinking at the top of the foreign office by 1919, he was not directly involved in this process, continuing his work as a member of parliament in the meantime. However, as noted above, the war continued to spur his vision of international co-operation at sea. Consequently, following the armistice of November 1918, Mackinder published a book aimed at the 'peacemakers' who would shortly assemble in Paris to conclude the war and bring the League of Nations project to fruition. This book, titled Democratic Ideals and Reality: a Study in the Politics of Reconstruction joined by the liberal 'peninsular' powers, France and Italy. China could also 'be regarded as advance guards of British, American, and Japanese sea-power'. Mackinder still viewed imperial unity as an important endeavour, but as with Corbett and Kerr, his idea of Greater Britain now merged completely with the League of Nations project. During the war the Dominions had achieved 'the relations of equality and … of independency', and would soon take 'their place as units of your League'. Yet within the League, the units of the British empire must be able to act in conjunction 'under a single strategical command' so that they may counterbalance the increasing power of the U.S.A., so maintaining harmony between the League's two dominant sea powers. Mackinder also cautioned that the League must retain its flexibility, envisaging new blocs of Scandinavian or South American powers joining in the future. 120 On the other hand, the 'World-Island' would remain a latent threat. If a continental power could unify it, it would pose a serious challenge to the 'islanders'. As Mackinder put it, 'Who rules East Europe commands the Heartland: Who rules the Heartland commands the World-Island: Who rules the World-Island commands the World'. This is perhaps the most famous Mackinder quote of all. Yet it has been taken out of context in previous studies, usually furnished as proof that the 'Columbian epoch' had ended and sea power was doomed to irrelevance at the end of the First World War, not least because it reconfigured Sir Walter Raleigh's dictum that command of the sea meant command of the world's trade, and therefore the world. 121 On the contrary, this was written as a warning to the peacemakers in Paris -to be recalled 'when our Statesmen are in conversation with the defeated enemy' -not a statement about the inevitable waning of sea power. He did note the 'ever-increasing strategical opportunities to land-power as against sea-power', but he argued that the victorious 'Islanders' could act now to reorganize the international system and ensure that their sea power remained capable of counteracting the 'continentals'. He explained that unifying the 'World-Island' remained 'the great ultimate threat to the World's liberty so far as strategy is concerned', so the peacemakers must 'provide against it in our new political system'. As he put it, 'Now is the time, when the Nations are fluid, to consider what guarantees based on Geographical and Economic Realities, can be made available for the future security of mankind'. Otherwise, it may be that they had 'headed off that danger in this War, and yet [left] by our settlement the opening for a fresh attempt in the future'. 122 Mackinder set out a number of measures that the League must take. First, on the 'World-Island', it should use this opportunity to create 'a balance as between German and Slav, and true independence of each', and establish a 'Middle Tier' of powers in Eastern Europe. This would prevent Germany and Russia from uniting and conquering Eastern Europe -the 'Heartland' -which held the key to controlling the 'World-Island'. This could be done in part by reducing Germany 'to its proper position in the world', rather than simply 'to trust to anything that may happen at Berlin; we must be secure in any case'. This would create 'the conditions precedent to a League of Nations'. The League should then establish its own dominance over international order, and this region specifically -it must act as 'the supreme organ of united humanity, [and] watch closely 120  the Heartland and its possible organisers'. To do this, Mackinder argued that certain limitations on sea power during the conflict ought to be removed through political reorganization and international collaboration. During the war the Royal Navy had failed to gain access to either the Baltic or Black seas. This could now be remedied under the aegis of the League, and he suggested that 'the League of Nations should have the right under International Law of sending War fleets into the Black and Baltic Seas'. These fleets would act as the sanction of the League, enabling it to intervene in the Heartland if necessary to safeguard the 'Islanders' and prevent the conquest of the 'World-Island'.
To underscore this, Mackinder proposed making Constantinople 'the Washington of the League of Nations' -its capital -enabling the League to 'weld together the West and the East, and permanently penetrate the Heartland with ocean freedom'. This is the critical line in Democratic Ideals and Reality, revealing not simply Mackinder's conception of the Heartland and 'World-Island', but its relationship to sea power. The navies of Greater Britain, the United States and their allies would be the chief strategic tool of the League of Nations in this new world order, and the international system would be set up to guarantee the primacy of the 'Islanders' and their sea power. To further cement this, Mackinder also proposed that other key strategic positions across the globe should remain in the possession of Britain and the U.S.A. -namely 'Panama, Gibraltar, Malta, Suez, Aden, and Singapore' -to ensure the League of Nations' control over the global commons. 123 While revisiting Democratic Ideals and Reality nuances our understanding of Mackinder's strategic thought, in 1919 it received less attention than his 1904 lecture. Without being in a position of influence, like Corbett, it was harder for him to make himself heard. However, as seen above his ideas were nevertheless similar to those being discussed in Whitehall. Moreover, Mackinder had not been forgotten by his powerful friends. In December 1919, on the basis of his work, the foreign office -now headed by Lord Curzon -sent Mackinder to South Russia as a high commissioner. From this position he attempted to influence the cabinet's policy on issues contained within Democratic Ideals and Reality. The critical issue of the League of Nations, however, had already gone awry. 124 By 1919 a number of key British maritime strategic thinkers shared similar visions for the post-war world. Britain would create a League of Nations with its main allies, the United States and France. The Dominions would enter as increasingly independent states. The League would operate predominantly as a collective security system that would enforce peace globally -it would not merely be a body for discussion or arbitration. The joint sea power of these states would be the sanction of the League, largely through the use of economic pressure, or blockade. Jon Sumida has previously noted how Alfred Thayer Mahan's vision of a naval consortium looked not dissimilar to the North Atlantic Treaty Organization formed after the Second World War, stating that Britain's decline by the middle of the twentieth century saw its 'subsumption into a politically and economically preeminent conglomerate of associated states' (albeit in an era where air power and the atomic bomb had fundamentally altered the strategic dynamic between land power and sea power). 125 Yet, as this article has demonstrated, British designs for international co-operation at sea are even more significant when seeking to understand the long-term origins of these ideas. The ideas of strategic thinkers -especially Corbett and Mackinder -meshed with those of the British foreign policymaking elite, with whom they interacted closely.
It is important to note that the League of Nations envisaged by the likes of Corbett and Mackinder failed to materialize. They were far from the only visionaries who were disappointed by the outcome of the events of 1919. As Stephen Wertheim has shown in 'The league that wasn't', certain American ideas for a 'legal-sanctionist League' that also relied on the use of force did not come to fruition either. 126 While Lord Robert Cecil, who managed British league policy at the Paris Peace Conference, was pleased to see that American ideas were in accord with those set out in the Phillimore report, other obstacles emerged, preventing the creation of a maritime-powered league for enforcing peace. One significant problem proved to be French objections to efforts to develop the sanction of sea power at the expense of large standing armies. Paris's preference was for a League of Nations Army, rather than a League of Nations Navy. The other problem was, of course, the U.S.A.'s ultimate decision not to join the League. Without the Americans, a system of sanctions based on sea power and economic pressure could not function effectively, fatally wounding the project. 127 While the arguments advanced here help to expand the small but important literature on the driving role played by British policymakers and strategic thinkers in the creation of the League of Nations, especially by highlighting the role of sea power in these visions, this article has also offered a reinterpretation of two elements of British grand strategic thought in the late nineteenth and early twentieth centuries. Firstly, solutions to the problem of imperial defence looked not exclusively to Greater Britain, but also to broader international co-operation at sea, an aspect that has been neglected in previous studies. Secondly, there was less doubt about the continued utility of sea power in this era than is often claimed by historians, who tend to cite Halford Mackinder's ideas. What was needed, however, was improved organization to enable maritime states to effectively counter continental rivals and the enhanced mobility offered by railways networks. As the examination of Mackinder's major works here has shown, even hethe supposed prophet of the coming of land power -remained a staunch advocate of sea power. His warnings were instead intended to spur policymakers towards creating a more internationalized sea power to safeguard the British empire and fellow 'Islanders'. Indeed, Mackinder remained convinced of the utility of sea power and the importance of international co-operation to maintain peace. He wrote on the subject one final time, in the middle of the Second World War, reflecting, 'What a pity the alliance, negotiated after Versailles, between the United States, the United Kingdom and France was not implemented! What trouble and sadness that act might have saved!' 128 126 S. Wertheim, 'The league that wasn't: American designs for a legal sanctionist League of Nations and the intellectual origins of international organization, 1914-1920', Diplomatic History, xxxv (2011), 797-836. 127 For a full account of these developments, see Halewood, 'Internationalising sea power', pp. 268-96. 128 H. J. Mackinder, 'The round world and the winning of the peace', Foreign Affairs, xxi (1943), 595-605, at p. 603.