This essay originally appeared under the title ‘Alfred Thayer Mahan,geopolitics and grand strategy‘ in ‘The Return of Geopolitics’, Bokförlaget Stolpe, in collaboration with the Axel and Margaret Ax:son Johnson Foundation, 2019.

Alfred Thayer Mahan (1840–1914) stands out as one of the foremost thinkers on naval warfare, strategy, and international politics. Mahan’s reputation as a strategic thinker rests primarily on his famous books about the influence of sea power on the world and its affairs. Scholars examining Mahan’s writings tend to concentrate on these histories about naval operations during the great wars between the end of the 17th and the beginning of the 19th centuries. As a consequence, Mahan is now best remembered as a naval historian, analyst of warfare in the maritime domain, and theorist of sea power.

But this perspective on Mahan is too narrow. In addition to his contribution to the study of naval history and operations, Mahan was a student of international relations and a policy analyst. He was a celebrated and prolific writer for almost a quarter of a century, writing extensively on international relations. He failed, however, to provide his readers with a systematic treatment of his own views on international relations, geopolitics, and grand strategy. His more famous historical writings, highlighting naval operations, are emphasised in examinations of his thought, while his theories about international politics are relatively neglected. This neglect is unfortunate because Mahan was a seminal thinker on international politics and strategy. To use the language of modern-day international relations theory, Mahan’s thought belongs within the realist tradition for the study of relations between states. This tradition traces its lineage back to Thucydides, and includes such prominent modern thinkers as Hans Morgenthau and Henry Kissinger. Indeed, Mahan was a close reader of Thucydides. Many of Mahan’s tenets about world politics and strategy are mainstays of contemporary international relations theory.

First, Mahan saw anarchy as a distinctive attribute of world politics. Since no supranational organisation existed that could control the international system, individual states needed to provide for their own security in a Darwinian struggle for survival. Because states struggled to find security, Mahan was dubious of their ability to promote cooperation between themselves by peaceful means. Arbitration agreements between states and the establishment of norms for conduct in the international arena were likely to work only so long as the issues at stake were limited. Once a state saw that its important interests were threatened, however, international agreements to promote cooperation could not take the place of armed force in providing for its security. Nor did Mahan think that the international system was likely to change in the near future. His scathing comments on Norman Angell’s The Great Illusion show how far Mahan was from the view that great power rivalries were atavistic and suicidal. Mahan argued that ‘the entire conception of the work is itself an illusion based on a profound misreading of human action’. So long as human nature remained unchanged, Mahan thought that the threat of war could never be banished from international relations. In Mahan’s view, the best way to prevent war was to be so well-armed that potential adversaries would be deterred from risking a conflict.

Second, Mahan viewed hierarchy as a distinguishing feature of world politics, and the international system was directed by the decisions of the great powers. He contended that the great commercial states in particular would play a leading role in world politics because of the wealth they generated from international trade. To Mahan, Britain’s leadership of the international political system during the 19th century rested in large part on its position as a trading state, its financial strength, colonies, and manufacturing. Britain’s naval strength protected this global system.

Third, Mahan theorised from his study of history that the cause of war and change in world politics was rooted in underlying shifts in the power relationships between states. Thus, the international system’s leading states had in the past been challenged by more rapidly growing powers, and these challenges carried with them the potential for war. During the period examined by Mahan in his histories of sea power, Spain, the Netherlands, France, and England had struggled with one another for leadership of the international system. In the decade before the First World War, Mahan saw the rise of Germany as the major challenger to Britain’s leading position in world politics. Mahan considered the decline of British power in the face of challenges from other great powers as the cardinal feature of the international system in the early 20th century.

Fourth, Mahan was concerned with the balance of power. It was an important tenet of his views on world politics that the great powers needed to prevent any one of their number from achieving hegemony within the international system. Mahan, an American, was concerned not only with the European balance of power but with the global equilibrium. The imperial rivalries between great powers in Asia and Latin America were linked with the European balance in a global system. In his assessment of power balances between states, Mahan gave prominence to five indicators: territory, population, armed forces, commerce, and the ability of governments to develop and carry out long-range planning to mobilise their country’s resources.

A fifth factor that was prominent in Mahan’s thought about world politics and strategy is that competing states adopt similar strategic doctrines and force structures. In the early 20th century, this principle was nicely illustrated by the general competition between the great powers in the building of battleships and their adoption of the strategic doctrine of battle-fleet concentration. Mahan attached a great deal of importance to the relationship between a country’s foreign policy and its naval power. An aspiring hegemon, eager to pursue an expansionist foreign policy – or a country trying to contain the expansion of rivals – required naval power. Thus, Mahan gave particular attention to the great power battleship build- ing rivalries and the strategic doctrines guiding the deployment of their navies in his analyses of developments in world politics.

He wrote extensively on naval strategy, history, and international relations. His writings emphasise the importance of geography in shaping the strategic choices of the great powers and in determining the outcome of their rivalries. Examinations of geopolitical rivalries between sea powers and continental states appear throughout his writings.

Mahan thought that world politics in the 20th century would be characterised by a global rivalry involving the great powers in a quest for commercial and naval supremacy. These struggles for empire, world power, and naval mastery were viewed by Mahan and others as a 20th-century replay of the wars that he had described in his volumes, The Influence of Sea Power Upon History, 1660–1783, and The Influence of Sea Power Upon the French Revolution and Empire, 1793–1812. During the course of these struggles, dramatic shifts were likely to take place in the power balances between the great powers.

In particular, Mahan was concerned with Britain’s ability to hold its position in world affairs against rising great-power challengers. It was an axiom of world politics at the turn of the century that the imperial rivalry between Britain and Russia throughout Asia and the Middle East – the so-called ‘Great Game’ – must sooner or later result in a diplomatic showdown and perhaps war. A corollary to this axiom held that Britain would not be able to contain Russia’s expansion in Asia without the support of major allies.

In the United States, such prominent national leaders and commentators on world affairs as Theodore Roosevelt, Henry Cabot Lodge and Brooks Adams, as well as Mahan, subscribed to this axiom and its corollary. This group wanted the US to take a more active role in world politics in support of Britain’s position. Brooks Adams, in his book America’s Economic Supremacy, published in 1900, advocated that ‘America must more or less completely assume the place once held by England, for the United States could hardly contemplate with equanimity the successful organisation of a hostile industrial system on the shore of the Pacific, based on Chinese labour.’

Mahan agreed with this assessment, arguing that the United States should align itself with Germany and Japan to assist Britain in containing Russia. This bloc of sea powers should seek to prevent Russia from gaining ‘preponderant political control’ of China. This historical precursor to what, after 1945, would be called a strategy of containment failed to come about. The Russo-Japanese War of 1904–05 revealed that Russia’s power had been overestimated.

Russia’s defeat, however, did not mean that Britain’s position was secure from challengers. In place of the Russian danger, Germany’s rise as a great naval power and Japan’s success over Russia heightened Mahan’s concern about the balance of power in Europe and Asia. Far from being united in purpose, the coalition of sea powers – Britain, Germany, Japan, and the United States – that Mahan had envisioned in The Problem of Asia were rivals on the world stage. In Mahan’s view, Germany had emerged by 1908 as the most serious challenger to Britain. Mahan told his readers: ‘The rivalry between Germany and Great Britain today is the danger point, not only of European politics, but of world politics as well… No such emphasised industrial and maritime competition between two communities has arisen since the time of Cromwell and the later Stewart kings, when England wrested from Holland her long possessed commercial supremacy, supported by a navy until then unconquered.’

What political and strategic indicators led Mahan to this assessment? One factor was Germany’s rapidly rising population and industrial production. To Mahan, Germany’s dramatic demographic and industrial growth meant that it would demand overseas territories as an outlet for its growing population and as markets for its products. But perhaps the single most important indicator that triggered Mahan’s alarm about Germany was that country’s naval challenge to Britain. Germany’s stated programme of naval construction and its decision to follow the lead of Britain and the United States in building ‘all-big-gun’ or dreadnought battleships showed the seriousness of the German challenge. Mahan pointed out: ‘The huge development of the German Navy within the past decade, and the assurance that the present rate of expenditure – over $20 million annually – will be maintained for several years to come, is a matter of great international importance.’ Mahan saw an intimate connection between Germany’s industrial growth, its rise as a naval power, and its drive for imperial expansion. As Mahan put it, there is ‘an inevitable link in the chain of logical sequence: industry, markets, control [of overseas territories], navy bases’.

The famous 1909 ‘naval panic’ in Britain heightened Mahan’s concern about Germany’s foreign policy goals. He tried to alert his American readers to the political significance of the growing German battle fleet in an article for Collier’s Weekly, entitled: ‘Germany’s Naval Ambition: some reasons why the United States should wake up to the facts about the Kaiser’s battleship-building programme – Great Britain’s danger exaggerated, but not her fright’. He reminded his readers of the German involvement in Venezuela in 1902 – ‘a condition almost sure to arise again’ – and warned that Germany would ‘have the whip hand’ in a future crisis if it possessed ‘a decisively superior navy’. Mahan asked whether the Monroe Doctrine should be ‘dependent upon the uncertain indulgence of a foreign state, which is notoriously thirsting for colonisation in the supposed interest of racial development?’ Only by building ‘a navy adequate to prevent such humiliation’ could the United States be prepared for the crisis to come. Mahan’s biographer Robert Seager described his subject as being, in the years between 1909 and his death on the 1st of December, 1914, ‘a journalistic Paul Revere’, alerting his English-speaking audience ‘to the fact that the Germans were coming’.

Germany’s naval and colonial ambitions led Mahan to advocate that the United States should support Britain in defeating this challenge. Why did Mahan champion this course for US foreign policy? Mahan might have recommended, for example, that the US adopt a foreign policy of the free hand and attempt to play Britain and Germany off against each other.

This is what Germany’s foreign policy attempted to do at the turn of the century when Britain and Russia were rivals in Asia. By holding the balance of power between London and St Petersburg, Prince Bernhard von Bülow, Germany’s foreign secretary and later chancellor, wanted to increase German prestige and influence in world politics. But instead of suggesting that the United States follow a similar strategy, seeking to exploit the growing Anglo-German antagonism, Mahan advocated that it help Britain contain German expansion. Why did Mahan, whose writings reveal such a pronounced Darwinian character, not call for the United States to take advantage of Britain’s embarrassment and help partition the British empire, thereby establishing the US as the leading world power? Answering these questions helps shed some light on Mahan’s theories about grand strategy and geopolitics.

First, Mahan believed that cultural and ideological affinities promoted cooperation between Britain and the United States. Britain’s heritage was part of America’s history. One consequence of these common traditions was that the governments in both countries were committed to promoting ‘the liberty of the individual’, as Mahan put it in his book, The Interest of America in International Conditions. This common heritage and democratic government acted to dampen their rivalry. Mahan, then, can be viewed as subscribing to what is now referred to as the democratic peace theory.

Second, Mahan did not see where Britain represented a threat to the United States. To Mahan, Britain was a satiated power, which was not likely to challenge the US in the Western Hemisphere. Britain’s actions in acquiescing in the control of the Panama Canal by the United States demonstrated this proposition. Moreover, Canada was ‘open to land attack’, and thus Britain possessed a vulnerability that the United States could exploit to check British ambitions. Britain, then, had already conceded hegemony to the US in the western hemisphere and was playing the main role in upholding the balance of power throughout Europe and Asia.

Third, in Mahan’s opinion, the rapid collapse of British power would result in the strengthening of Germany’s position. Unlike Britain, more a satiated power, Germany was in Mahan’s assessment aggressive, expansionist, and seeking new colonies. The growth of German power might result in a challenge to the United States’ position in the western hemisphere. Britain and the US had a common interest in working to preserve the existing international order from which both benefited.

Given these considerations, Mahan argued that the United States was better off strengthening Britain’s strategic position rather than undermining it. By aligning itself with Britain, the US would be in a better position to contain German expansion. Faced by an Anglo-American strategic alignment, Germany might be deterred from seizing colonies in the western hemisphere. As part of this alignment, the United States needed to develop a powerful fleet.

Mahan’s sympathies for Britain were not uncommon for naval officers of this era. The General Board of the Navy, for instance, suggested a naval alliance with Great Britain directed against Germany. In a letter to Secretary of the Navy, Charles Bonaparte, dated September 28, 1906, the General Board warned that Germany would strike to seize colonies in the western hemisphere as soon as its fleet was ready. Since British leaders were also alarmed by German naval and colonial expansion, the General Board advised the Roosevelt administration to consider an under- standing with Britain along the lines of the Anglo-Japanese Alliance of 1902: if the United States faced only Germany, Britain would remain benevolently neutral; but if Germany attacked with the aid of an ally, Britain would enter the war on the side of the United States. The General Board believed such an agreement would deter Germany from attacking across the Atlantic because its own home coasts would then be denuded of battleships and open to British attack. In the General Board’s opinion, ‘the two English speaking nations seem destined to exert a great influence on the further progress of the world, and the conduct of war.’

A formal alliance was outside the bounds of practical politics within the United States, and Mahan urged instead a foreign policy of tacit cooperation with Britain. This alignment entailed that the US build a powerful navy, while at the same time eschewing any policy of provoking a naval competition with Britain. It is important to note that Mahan did not urge that the US acquire a battle fleet as large as that maintained by Britain. What Mahan wanted was for the United States to direct its energies to keeping abreast of Germany in modern battleships. Given Germany’s naval ambitions, the cost of achieving even this goal was going to be substantial. Mahan also advocated that the United States mass its force of battleships on the east coast, where it could be more readily assembled to defeat any German move to seize territory in the western hemisphere.

Mahan sought to impress upon American readers the threat posed by the German battle fleet for the security of the United States. He warned again and again that the growth of the German battle fleet was rapidly overturning Britain’s naval supremacy. In 1910, in The Interest of America in International Conditions, Mahan told his fellow countrymen that they could not remain unconcerned at this German challenge to Britain because it might prove successful. Americans must, he wrote, ask themselves ‘whether they can afford to exchange the naval supremacy of Great Britain for that of Germany; for this alternative may arise’. Once the European balance was overturned, ‘a German navy, supreme by the fall of Great Britain, with a supreme German army able to spare readily a large expeditionary force for over-sea operations, is one of the possibilities of the future.’

In Naval Strategy, published in 1911, Mahan drew attention to the importance of the decline of British power for the United States. ‘The power to control Germany does not exist in Europe, except in the British Navy.’ he wrote, ‘And if social and political conditions in Great Britain develop as they now promise, the British Navy will probably decline in relative strength, so that it will not venture to withstand the German on any broad lines of policy, but only in the narrowest sense of immediate British interests… for it seems as if the national life of Great Britain were waning at the same time that of Germany is waxing.’ Mahan argued that ‘it is this line of reasoning which shows the power of the German Navy to be a matter of prime importance to the United States’. Germany might be able to use its fleet as a political lever to keep Britain and the US from acting in concert with each other to maintain the existing balance of power. By separating Britain from the United States, Germany might seize an opportunity to acquire territory in the Western Hemisphere.

For Mahan, then, it was essential that Britain and the United States attempt to defeat Germany’s naval challenge. But Mahan was not sanguine that either Britain or the US – despite his estimation that they possessed superior economic resources – would be able to keep ahead of Germany in this naval rivalry. Mahan was concerned that governments representative of the people might not be able to pursue a viable long-term strategy. Despite their superior resources, Britain and the US appeared incapable of harnessing them. Germany’s government, on the other hand, seemed to Mahan to be better able to mobilise the resources of the country to support its foreign policy aims. ‘The two English-speaking countries’, Mahan wrote, ‘have wealth vastly superior, each separately, to that of Germany; much more if acting together. But in neither is the efficiency of the Government for handling the resources comparable to that of Germany.’ Mahan argued that ‘the habits of individual liberty in England or America [do not] accept, unless under duress, the heavy yoke of organisation, of regulation of individual action, which constitutes the power of Germany among modern states’. Mahan, then, questioned whether democratic governments would be able to make and carry out a long-term strategic plan.

It was Mahan’s fear that the United States would not build a sufficient number of modern battleships to match the German programme. Mahan lamented in a letter written in 1909: ‘The German Navy will in 1912 – in three years – have a stronger battle fleet in A-B-G [all-big-gun] ships than we. What then shall we say, upon what shall we rely, if she, on occasion arising, defy us in the Monroe Doctrine? How do we propose to keep that national idol on its feet without a superior navy?’

The US Navy’s General Board shared Mahan’s anxiety that Germany was rapidly outstripping the United States in naval strength. The General Board argued that the US needed to maintain a condition of rough parity with Germany’s battle fleet. But no political consensus existed in the United States to meet this standard of naval strength, and so keeping pace with Germany in the building of capital ships.

The result of losing the naval arms race with Germany might be German colonial gains in the western hemisphere. For the readers of The New York Times on April 2, 1912, Mahan even devised peace terms that Germany might impose on the United States at the conclusion of some future war. He wrote: ‘What terms? Well, to name three principal, omitting others: the surrender of the Panama Canal, the admission of Asiatic labour immigration, and the abandonment of the Monroe Doctrine. These may be stated as (1) the surrender of a vital link in our coastwise communications, the principal end for which the Canal was undertaken; (2) the constitution of a population predominately Asiatic on the Pacific slope west of the Rocky Mountains – a new race problem; and (3) the suppression of a national policy, the salutary aim of which has been to exclude foreign wars from propagation to the American Hemisphere.’

When war engulfed Europe in the summer of 1914, Mahan worried that this prediction might soon come about if Germany defeated its enemies. He told interviewers from The New York Evening Post: ‘If Germany succeeds in downing both France and Russia, she gains a respite by land, which may enable her to build up her sea power equal, or superior to that of Great Britain. In that case the world will be confronted by the naval power of a state, not, like Great Britain, sated with territory, but one eager and ambitious for expansion, eager also for influence. This consideration may well affect American sympathies.’

To one of his English correspondents, Mahan expressed the fear that ‘if Germany wins by a big margin she is likely to be nasty to us [in the United States]’. Thus, Mahan’s sympathies lay squarely with Britain in the Great War at the time of his death. Moreover, he deeply resented the Woodrow Wilson administration’s gag order, which prevented him from arguing the case for containing German power.

Mahan’s views about the threat posed by German imperial and naval ambitions led him to advocate the concentration of the American battle fleet in the Atlantic as a strategic necessity if the US was to stave off defeat in case of a war with Germany. The General Board agreed that Germany represented the ‘more formidable’ enemy. Concentration against the German battle fleet constituted the strategic fulcrum of United States naval planning. Whenever asked for his views, Mahan never wavered in his conviction about the danger posed by Germany. Since he feared that a fickle and ignorant public might pressurise an administration into dividing the fleet, he made repeated efforts to publicise his views on strategy. The young assistant Secretary of the Navy in the Wilson administration, Franklin D Roosevelt, also thought it important to educate the public about naval strategy and geopolitics. He wrote to Mahan in the spring of 1914 to enlist his support through writing ‘an article or articles’ because his ‘voice will carry more conviction than that of anybody else’. Roosevelt thought that ‘the people can be educated, but only if we all get together ahead of time and try to show the average “man in the street” the military necessity of keeping the Fleet intact.’ With the outbreak of war in Europe, Mahan urged Roosevelt ‘that the fleet should be brought into immediate readiness, and so disposed as to permit of very rapid concentration’.

Mahan made a signal contribution by helping to inform his fellow countrymen about world politics and strategy. He attempted to highlight the importance of the balance of power for the security of the United States, and that emerging geopolitical threats to Britain’s world position also posed a danger to American security. Mahan argued that the US needed to play a role – an increasingly important role – in upholding the balance of power on a global scale. Mahan was warning his American readers that ‘the age of free security’ – to use the apt phrase of the historian C Vann Woodward – was passing away. The security of the United States could no longer depend, as it largely did during the 19th century, on latent military power buttressed by the natural moat formed by the Atlantic and Pacific oceans and the icebound wastes of the Arctic. Instead, the United States was moving from an era of inexpensive security to expensive insecurity – from ‘the age of free security’ to the age of ‘the national security state’. The signal contribution made by Mahan in educating the American public and its leaders about world politics and strategy should not be overlooked in the study of his writings.

Today, Mahan’s writings have enduring value for understanding the unfolding dynamic of international relations. The 21st century is witnessing what the author and broadcaster Fareed Zakaria calls ‘the rise of the rest… the distribution of power is shifting, moving away from American dominance’. In Zakaria’s view, this transformation of power balances augurs a ‘post-American world’. These underlying changes in the inter- national system resemble Britain’s declining power position at the beginning of the 20th century. And, what Brooks Adams wrote in 1900 in America’s Economic Supremacy seems even more relevant in our time than his own – that ‘on the fate of China may, perhaps, hinge the economic supremacy of the next century’.

China’s rising power and foreign policy ambitions pose a particularly ominous problem because they threaten a replay of past violent struggles for security and mastery, as occurred before the First World War. Mahan would recognise these dangerous undercurrents in the international security environment. As the American author, Robert Kaplan has noted: ‘Tellingly… the Chinese avidly read [Mahan]; the Chinese are the Mahanians now.’ The naval build-ups taking place in Asia follow an iron logic of competition that Mahan examined in his writings. Chinese strategists can draw, from Mahan and the American experience, how a rising power can build up anti-access, area-denial capabilities to fight on the maritime domain as a way to assert regional dominance. Meanwhile, China’s growing ability to fight on the high seas would likely have Mahan calling for a pivot to Asia, a countering American arms build-up, and an effort by Washington to build a coalition to contain Chinese power. Both American and Chinese strategists can thus still draw upon Mahan as a guide for their actions in the international arena. The question is, with what result?