“The actual balance of political power at any given time is… the product, on the one hand, of geographical conditions, both economic and strategic, and, on the other hand, of the relative number, virility, equipment and organization of the competing peoples.”

Mackinder’s “pivot” paper caused one member of the Royal Geographical Society to “look with regret on some of the space which is unoccupied here.” Unfortunately, as W. H. Parker has pointed out, “in the English-speaking world Mackinder’s paper lay forgotten . . . for thirty-five years.” It was only during and after the Second World War that Englishmen and Americans began to appreciate the wisdom and prescience of Mackinder’s “pivot” paper and his 1919 masterpiece, Democratic Ideals and Reality.

A few months before he delivered the “pivot” paper to the Royal Geographical Society, Mackinder was appointed the director of the London School of Economics, a post that he held until 1908. In 1910 he was elected to the House of Commons, where he served until 1922. In 1919, as civil war raged in Russia, Lord Curzon, the Foreign Secretary, chose Mackinder to be British High Commissioner for South Russia. In that post, Mackinder promoted the idea of a British-supported anti-Bolshevik alliance because he feared that if the Bolsheviks consolidated their control of Russia “there is… great risk that such a weapon may be forged as may become a danger to the world.” “[T]here is to-day,” he warned, “a growing threat from Moscow of a state of affairs which will render this world a very unsafe place for democracies. . . .”⁹ Among British policy makers of the time, only Winston Churchill voiced strong support for Mackinder’s anti-Bolshevik strategy.

During his directorship of the London School of Economics and his stay in Parliament, Mackinder continued to think and write on geography and world affairs. His articles and books included: “Man-Power as a Measure of National and Imperial Strength” (1905), Our Own Islands: An Elementary Study in Geography (1906), “On Thinking Imperially” (1907), “The Geographical Environment of Great Britain” (1908), The Rhine: Its Valley and History (1908), “Geographical Conditions Affecting the British Empire” (1909), “The Geographical Conditions of the Defence of the United Kingdom” (1909), “The New Map” (1915), “Some Geographical Aspects of International Reconstruction” (1917), “This Unprecedented War” (1917), and “The New Map of Europe” (1918).

Shortly after the end of the First World War, Mackinder wrote ,¹⁰ arguably the most important work on international politics ever written by a geographer. Here Mackinder greatly expanded on his 1904 “pivot” paper, drawing on recent lessons learned from the Great War. In the book’s preface, referring to the continuing relevance of the ideas expressed in the “pivot” paper, Mackinder opined that “the war has established, and not shaken, my former points of view.” In the two hundred or so pages that followed, Mackinder presented a masterful synthesis of historical and geographical analyses that has withstood the test of time.

Early in the book, Mackinder emphasized the paramount importance of geography to the study of history and global politics. “The great wars of history,” he wrote, “are the outcome, direct or indirect, of the unequal growth of nations, and that unequal growth… in large measure … is the result of the uneven distribution of fertility and strategical opportunity upon the face of the globe.” The “facts of geography” indicated to Mackinder that “the grouping of lands and seas, and of fertility and natural pathways, is such as to lend itself to the growth of empires, and in the end of a single world empire.” In order to prevent future world conflicts, he advised, “we must recognize these geographical realities and take steps to counter their influence.” He proposed to reveal those “geographical realities” by measuring “the relative significance of the great features of our globe as tested by the events of history….”

Mackinder pointed out that although the “physical facts of geography have remained substantially the same during … recorded human history,” it was only at the beginning of the twentieth century that the globe became, in political terms, a “closed system.” “Every shock, every disaster or superfluity,“ he wrote, ”is now felt even to the antipodes…. Every deed of humanity will henceforth be echoed and re-echoed in like manner round the world.”

In geographical terms, Mackinder’s world as sketched in Democratic Ideals and Reality consisted of the following: (1) one ocean covering nine-twelfths of the globe; (2) one great continent encompassing Europe, Asia and Africa; and (3) several smaller islands including Britain, Japan, North America, South America and Australia. The one great continent, which Mackinder called “the World-Island”, he further subdivided into six regions: the European coastland (Western and Central Europe), the Monsoon or Asian coastland (India, China, Southeast Asia, Korea and eastern Siberia), Arabia (the Arabian peninsula), the Sahara (North Africa), the Southern Heartland (Africa south of the Sahara), and, most important, the Heartland (the northern-central core of Eurasia which he had called the “pivot region” in his 1904 paper).

Mackinder showed the significance of the position of the Eurasian-African “World-Island” on the globe by geo-historical analogy. The "World-Island” was to North America, he explained, what Greece under the Dorians had been to Crete, and what the Roman Empire had been to Britain, i.e., an unchallenged peninsular land power versus an insular sea power. In both of those instances of history, strongly-based unchallenged land power defeated the less strongly-based sea power. But it was not simply a case of land power being superior to seapower. The victorious land power had to be unchallenged by land, and had to possess sufficient resources to enable it to construct a fleet powerful enough to defeat the insular sea power. Absent those two conditions, a strongly-based insular power would prevail, as evidenced by the British defeat of Napoleon’s France, the latter of which, while possessing tremendous resources, faced a significant land power challenge to the east (Russia) which prevented it from harnessing those resources to overwhelm British seapower.

Indeed, in Mackinder’s view, the optimum geographical position combined insularity with greater resources, and that was precisely the position of the “World-Island.” Strategists, he explained, “must no longer think of Europe apart from Asia and Africa. The Old World has become insular, or in other words a unit, incomparably the largest geographical unit on our globe.” In the First World War, had Germany conquered Russia and France, “she would have established her sea-power on a wider base than any in history, and in fact on the widest possible base.” Although Germany lost the war, Mackinder cautioned, “must we not still reckon with the possibility that a large part of the Great Continent might some day be united under a single sway, and that an invincible sea-power might be based upon it?” “[T]hat,” Mackinder wrote, “is the great ultimate threat to the world’s liberty.”

The most strategically significant geographic feature of the “World-Island” was the Heartland, which Mackinder described as “a great continuous patch in the north and center of the continent… from the icy, flat shore of Siberia to the torrid, steep coasts of Baluchistan and Persia.” This region’s great rivers (Lena, Yenisei, Obi, Volga and Ural) emptied either into the frozen Arctic Ocean or inland seas (the Caspian and Aral), thereby rendering the Heartland “inaccessible to navigation from the ocean.” The Heartland also included a great “lowland” plain that formed “a broad gateway from Siberia into Europe,” which is suitable to highly mobile land power.

As in his 1904 “pivot” paper, Mackinder in Democratic Ideals and Reality, used history to illustrate the strategic significance of geography. He noted that beginning with the Huns in the fifth century, successive waves of mobile hordes emerged from the Heartland to conquer or threaten the coastlands of Europe and Asia. Those hordes, however, lacked sufficient manpower and organization to conquer the whole World-Island, or a large part of it (although the Mongols came close to doing so). Two modern developments—increased population and advanced means of overland transportation (railroads, motorcars)—threatened to upset the balance between land power and seapower, and constituted, in Mackinder’s words, “a revolution in the relations of man to the larger geographical realities of the world.”

Mackinder described how during the nineteenth century following the defeat of Napoleon and until the rise of the German empire, British sea-power sought to contain Russian land-power, a geopolitical struggle that has since been called the “great game.” Germany’s rise to world power after 1871 shifted the geopolitical focus of British statesmen and set the stage for the First World War. For Mackinder, the most important aspect of that war, for the purposes of strategy, was Germany’s near successful conquest of Eastern Europe and the Heartland. Had Germany discarded the Schlieffen Plan, remained nominally at peace with France and Britain, and directed all her efforts and resources eastward, the world would be “overshadowed by a German East Europe in command of the Heartland.” “The British and American insular peoples,” warned Mackinder, “would not have realized the strategical danger until too late.”

Mackinder perceived a consistent geographical basis for British policy during the “great game” and the First World War. “We were opposed to the… Russian Czardom,” explained Mackinder, “because Russia was the dominating, threatening force both in East Europe and the Heartland for a half century.” “We were opposed to the… German Kaiserdom, because Germany took the lead from the Czardom, and would have crushed the revolting Slavs, and dominated East Europe and the Heartland.” This strategic insight formed the basis of Mackinder’s memorable advice to the Western statesmen at Versailles: “Who rules East Europe commands the Heartland: Who rules the Heartland commands the World-Island: Who rules the World-Island commands the World.”

The postwar settlement and reconstruction was the focus of the final part of Democratic Ideals and Reality. Mackinder worried that failure by the statesmen at Versailles to construct an effective security system for Eastern Europe would mean that after the terrible sufferings of the First World War, the Western democracies “shall merely have gained a respite, and our descendants will find themselves under the necessity of marshaling their power afresh for the siege of the Heartland.” To those who argued that Germany’s defeat would alter the German desire for conquest and power, Mackinder sagely replied: “He would be a sanguine man…who would trust the future peace of the world to a change in the mentality of any nation.” To those who argued that peace would be secured by the new League of Nations and its professed ideals, Mackinder prophetically remonstrated: “No mere scraps of paper, even though they be the written constitution of a League of Nations, are, under the conditions of to-day, a sufficient guarantee that the Heartland will not again become the center of a world war.”