The Grand Strategy of the Roman Empire From the First Century A.D. to the Thirdby Edward N. Luttwak
(Baltimore: The Johns Hopkins University Press, 1976)
Placing Edward Luttwak's Grand Strategy of the Roman Empire in the category of a classic is bound to generate controversy, as did Luttwak's book when it was first published in 1976 (it was his doctoral dissertation at Johns Hopkins University SAIS). Some prominent scholars of Rome and the classical period dismissed the book as the product of an index-flipping amateur. They brought up particular inaccuracies and challenged many of its generalizations and interpretations. In the broader public policy arena, in the aftermath of Vietnam and the period of detente with the Soviet Union, those who wanted to pare down America's global role did not take well to sympathetic studies of imperial strategy, grand or otherwise. On the other hand, for those who took strategy seriously and who fretted over the decline of American power and will, Luttwak's emphasis on suasion and the economy of force too often seemed to offer a solution set that was too good to be true.
That said, Luttwak was clearly on to something. He put forward a challenging perspective on grand strategy, harkening in some ways to the realist perspective of men like Walter Lippmann, but also full of fresh insight. He raised the right sort of questions – new questions – even if he did not necessarily reach the right or only answer. He did so by outlining what he perceived to be the patterns of continuity and change in the strategic policies of the Roman Empire from Augustus to Diocletian. He concluded that the ancient Romans had an instinctive grasp of strategic logic embedded in their culture, which allowed not only continuity across changing regimes, but also for strategic evolution in response to a changing security environment.
Luttwak posed the central problem that grand strategy, in his view, properly seeks to address: "For the Romans, as for ourselves, the two essential requirements of an evolving civilization were a sound material base and adequate security. For the Romans, as for ourselves, the elusive goal of strategic statecraft was to provide security without prejudicing the vitality of its economy base and without compromising the stability of an evolving political order." Rome's enduring success, in Luttwak's opinion, reflected the high degree to which these conflicting imperatives were reconciled at the highest level of statecraft. "Roman security was not derived from tactical superiority on the battlefield, from superior generalship, or from a more advanced weapons technology. The superiority of the Empire was of an altogether more subtle order: it derived from the whole complex of ideas and traditions that informed the organization of Roman military force and harnessed the armed power of the empire to political purposes. The firm subordination of tactical priorities, martial ideas, and warlike instincts to political goals was the essential condition of the strategic success of the empire." The Romans, with rare exceptions, avoided the costly pursuit of purely tactical successes and purposeless victories. Especially in the early period of the Empire, military force was clearly recognized for what it was, an essentially limited instrument of power, costly and brittle.
The Romans understood that, when possible, it was best to conserve force and use military power indirectly as the instrument of political warfare. Together with money and manipulative diplomacy, the Romans deployed forces visibly ready to fight but held back from battle to foster disunity among those who might jointly threaten the empire, to deter those who would otherwise attack, and to control lands and peoples by intimidation – ideally to the point where sufficient security or even an effective domination could be achieved without any use of force at all. The Romans learned that most desirable use of military power was not military at all, but political. They conquered the entire Hellenistic world with few battles and much coercive diplomacy. The Romans understood all the subtleties of deterrence, and its limitations.
Above all, the Romans clearly realized that the dominant dimension of power was not physical but psychological -- the product of others' perceptions of Roman strength, rather than the use of this strength. The Roman siege of Masada, an otherwise unimportant place, was a calculated act of psychological warfare that revealed the exceedingly subtle workings of a long range security policy based on deterrence. The Romans did not bypass the fortress and starve out the Jews using a small blockading force, a course which would have attracted little attention. Nor did they storm the mountain, with the attendant loss of manpower and the risk of at least a temporary setback that might encourage resistance elsewhere. The full-scale siege operation was not cheap in terms of time or treasure, to be sure. But by engaging in a three-year operation to reduce the fortress by great works of engineering, the Romans must have made a great impression on those who might otherwise been tempted to contemplate revolt.
Luttwak identified three distinct systems of imperial security that integrated diplomacy, military forces, road networks, and fortifications, which were intended to serve a single objective. The design of each element reflected the logic of the whole. Each system was intended to satisfy a distinct set of priorities, themselves the reflection of changing conceptions of empire: hegemonic expansion for the first system; territorial security for the second, and finally, in diminished circumstances, sheer survival for the imperial power itself. Each system was based on a different combination of diplomacy, direct force, and fixed infrastructures. Each entailed different operational methods.
The system of what might be called the Republican Empire, or Julio-Claudian, derived its security along the frontier from client states and mobile armies. Around its core areas the empire was hegemonic in nature, with client states autonomously responsible for implementing the Roman desiderata and providing for the territorial security of the core areas out of their own resources. No Roman troops were ordinarily deployed in the client states or with the client tribes, but the stability of the system required a constant diplomatic effort both to ensure that each client was continually aware of the totality of Roman power (while being politically isolated from each other) and to maintain the internal and regional (i.e., inter-client) equilibrium of the client structure. Client states great and small were thus kept in subjection by their own perceptions of Roman power, and this deterrent force was complemented by positive inducements, notably subsidies.
Under this system, the Roman Army that the clients perceived as an undivided force of overwhelming strength was actually distributed in a vast circle around Rome. But these troops were still concentrated in multi-legion armies and were not committed to territorial defense, so they were inherently mobile and freely re-deployable. This flexibility resulted in vast disposable military strength, which could be used for further expansion were the front remained "open," as in Germany before A.D. 9 or Britain under Claudius. Owing to its hegemonic nature, the sphere of imperial control was limited only by the range at which others perceived Roman power as compelling obedience. The reach of Roman power and the costs of its military forces, therefore, did not need to be proportional. Further extensions of the empire, in a hegemonic mode, did not require increases in the military forces maintained. New clients added to the empire could be expected to respond to the same compulsion as did all the clients brought within the sphere of imperial control before them. Hence the economy of force and efficiency enjoyed by the Republican Empire. But this was a system whose goal was to enhance the security of the Roman heartland rather than to provide comprehensive, day-to-day security of the imperial territory and its populations.
The Antoine system, in use in one form or another from the Flavian era after A.D. 69 to the political crisis of the mid-3rd century, reflected the territorialization of the empire and the reorientation of its priorities. Defense was now based on "scientific" frontiers and preclusive (perimeter) defense. Armed forces were now everywhere deployed to secure the tranquility and therefore the prosperity of border lands, and a fortiori, of the interior. The military strength of the empire and its effective power were rigidly proportional, since strength was now largely used directly, not as a tool of political suasion. Clients remained, but they were much less useful than in the past: the task of maintaining territorial security was effectively shifted from weak clients to widely distributed frontier forces, while strong clients could no longer be tolerated, since their strength might now dangerously exceed that of the adjacent imperial forces, which were often stretched thin, at least on paper.
Nevertheless, the empire remained strong, and not the least of its strength was political. A real growing prosperity and a voluntary Romanization largely overcame the last vestiges of nativist disaffection and created a strong base of support for the unitary regime. Facing enemies widely separated from one another at the periphery, the empire could still send overwhelming powerful forces against them, since the tranquility of the provinces – and in places, elaborate border defense infrastructures – allowed peace to be temporarily maintained even with much-depleted frontier forces. The residual offensive capability was primarily useful as a diplomatic instrument; its latent threat served to keep the neighbors of the empire divided, if not necessarily obedient.
Nevertheless, the cultural and economic influence of Rome on the lives of all the neighbors of the Empire itself created a cultural and political bias for common action against it. Men who had nothing in common now acquired elements of a culture shared by all but belonging to none. Beyond the Rhine, the federation of border peoples that eventually turned into formidable multi-tribal agglomerations had begun. Opposed by the relentless force of cultural transformation, Roman diplomacy became less effective in keeping the enemies of the empire divided; and the system of perimeter defense, keyed to low-intensity threats, could not adequately contend with their unity.
The third system arose in response to the intractable combination of diplomacy and military problems whose consequences became manifest in the great crisis of the third century. The Romans devised an elastic defense, in which ad hoc field armies fought against barbarian coalitions deep within imperial territory; and later, under Diocletian, a shallow and structured defense in depth. These new defensive variants were not thought to be desirable. When local threats were defeated or suppressed, every attempt was made to return to the system of preclusive security.
Like the Antoine frontier establishment, the new system provided no short-term disposable surplus of military power either for offensive use or for diplomatic coercion, deterrent or compellent. The difference was that the this system no longer had a surge capability either, since the enemies of the empire were no longer kept on the defense by forward defensive tactics; instead, they were only contained. When the containment forces were reduced to muster ad hoc field forces, enemy penetrations occurred, and the remnant capacity to generate the image of power for the purposes of political suasion were irretrievably lost. The diplomatic relationships with external powers now reflected the local balance of forces, which did not always favor the empire on every sector of the perimeter.
With this, the output and input of the system were finally equated. The level of security provided became directly proportional to the amount of the resources expended on the army and on frontier fortifications. The great economy of force that made the unitary empire such an efficient provider of security was lost. It merely employed certain modest economics of scale over the alternative of independent regional states. And these economies of scale were not enough to compensate for the growing administrative inefficiency and venality. Loyalty to the idea of empire, and fear of the unknown, kept the system in place until organized barbarian states, capable of providing a measure of security in lands that had once been Roman, came to the fore.
— Patrick Garrity, September 24, 2010
An American Classic
The Diplomacy of Imperialism, 1890-1902
New York: Alfred A. Knopf, 1935, 2 volumes, reprinted 1951 (one volume).
by William L. Langer
During his tenure at Harvard University, Professor William L. Langer published a number of highly influential studies of diplomatic history and U.S. foreign policy, including an examination (with S. Everett Gleason) of U.S. isolationism and the domestic run-up to World War II. Langer also served as the Chief of the Research and Analysis Branch, Office of Strategic Services (1942-1945); special assistant for intelligence to Secretary of State Byrnes; Assistant Director of the CIA (1950-1952), where he helped organize the Office of National Estimates; and member of the President’s Foreign Intelligence Advisory Board (1961-1977).
Langer first made his name in academia with the publication of two major studies of 19th century European diplomacy European Alliances and Alignments, 1871-1890, published in 1931, and its follow-on, The Diplomacy of Imperialism, 1890-1902, originally published in 1935. Langer relied extensively on archival material that had not been available or had not been utilized by other scholars, including the diaries of the Russian Foreign Minister Count Vladimir Lamsdorff.
The Diplomacy of Imperialism is not an easy read nor does it contain a simple take-home message, although Langer believes that the basic outlines of the imperial struggle can be discerned (this outline is discussed briefly below). The volume is full of detail and events, individuals and agreements (or disagreements), which would have been familiar to an educated audience in the 1930s, but less so today. The contemporary reader will be struck with the complexity and fluidity of the diplomatic combinations and the shifting aims of the great powers what Langer refers to as the “interpenetration” of alliances. By Langer’s account, there is no straight line between the imperial rivalries of the 1890s and early 1900s and the alignments that led to World War I. Langer’s study is at the level of European Cabinet diplomacy, with relatively little attention to the particulars of those peoples coming under the sway of the European empires. (He does provide an extended, and controversial, treatment of the Armenian separatist movement, but this more in the context of a European, rather than an imperial, crisis.) But the great and would-be great empires are not billiard balls emperors and their ministers are at odds about the proper strategic course (and often divided even in their own minds). Cabinets are influenced by public opinion and by the popular Zeitgeist. Governments rise and fall. Policies zigzag and wobble. You need a scorecard to tell the players and their position on the field. Imperial diplomacy is a very messy business.
To touch on some of the overarching points of Langer’s narrative (he considers in detail particular conflicts and crises, including the Armenian question, South Africa and the Boer War, the great power conflict over Chinese sovereignty, and the competition over the Nile River valley):
During the previous period of European history (1871-1890), which might be entitled the Bismarckian System or the Hegemony of Germany, European relations were predominantly continental in character. But with Bismarck’s fall all that changed. William II’s refusal to renew the famous Reinsurance Treaty knocked the keystone from the European alliance structure. It restored to Russia a liberty of action which she did not want and paved the way to the (reluctant) conclusion of the Franco-Russian alliance, that odd ideological coupling of an unstable republican regime and an absolutist government whose principal ministers followed sharply divergent policy impulses. With the consummation of that grouping in 1894 a new era in European diplomacy may be said to have begun, for the Franco-Russian combination broke the preponderance of Germany and reestablished something like the balance of power on the Continent. But neither France nor Russia desired a confrontation with Germany. The Franco-Russian alliance, if anything, was directed against England.
With the two groups of powers evenly matched, the old European issues were reduced to a deadlock. For fully ten years, European interstate relations were in a state of flux. The old connections began to dissolve and on all sides there was an uncertain groping towards a new stability. There was no directness of policy and singleness of purpose, a condition which challenges the diplomatic historian to unravel the strands of an almost chaotic situation. There was an “interpenetration” of alliances, so that (in the words of an Italian historian) “allies acted as though they were adversaries, while members of opposing diplomatic systems acted as they were more [like] friends.”
To complicate matters further, the growing economic pressure and the increasing competition for markets among the great powers stimulated and facilitated that outburst of overseas expansion which we called imperialism (with the associated outburst of “navalism.”) The interests and energies of the great powers carried with them into the colonial field their traditional European rivalries but the exigencies of the situation often forced them to modify their time-honored policies.
Had the focal points of international relations continued to be the continent, England might well have acted as the fulcrum of the balance between the two rival combinations. As it was, she tended to become the object of attack for both groupings. England, the power that stood in the way of every nation that dreamed of expansion overseas, became the object of universal suspicion and distrust. The Franco-German opposition to the Anglo-Congolese Treaty, for instance, showed that England was isolated and that the two great groups of continental powers, unwilling to drift into conflict with each other, might very well cooperate against the one great power which stood aloof from both groups. Much of the globe was an English preserve and the British were not backward in advancing their claims to such regions as remained unappropriated. As businessmen the English would undoubtedly have preferred to continue as before, with the whole world as a market and with no very serious competitor. But now, with the growth of French and German colonies, there was an obvious danger that the British markets would be steadily restricted. Hence the emergence and sudden flowering of the movement for expansion among key segments of the British elite. The dynamic of expansion took over when Britain made certain critical decisions about the extent of their Empire and its lines of communication. Once the decision was made to stay in Egypt, for example, then the Nile had to be protected from encroachment by other imperial powers (particularly the French).
The English also felt they had to take over large blocks of territory to prevent markets from falling into the hands of exclusive rivals. Economic control was no longer possible, it seemed, without political control. This policy direction was reinforced by a sense of mission and the general atmosphere of conflict nurtured by the current ideas of evolution, as well as the sense that Germany and Britain were natural racial rivals. But at the same time, Britain’s far-flung possessions exposed her particularly to attack. As Africa and Asia came to play an ever-greater role in international relations, it was inevitable that England’s position should become more precarious. Summed up in a few words, the story of European international relations in the 1890s is the story of the assault of Russia and France upon the territorial position of Britain in Asia and Africa, and the story of the great economic duel between England and her all too efficient German rival.
Langer focuses particularly on the estrangement of England and Germany caused by their imperial rivalry. He concludes that in France and Russia the movement for expansion was essentially an artificial one, resting upon considerations of national prestige, drawing its support from a group of statesmen who looked to the future, from a relatively small number of explorers and colonial enthusiasts, and from a syndicate of bankers and speculators. (Langer here tends to gloss over the traditional British-Russian rivalry in Asia, which he regards as something quite different from the newly-developed imperial conflicts in the latter decade of the 19th century.) With Britain and Germany the situation was quite different. England was the industrial and trading national par excellence, depending for her food supply upon imports and literally living upon her foreign trade. Her position in the world was, in the 1890s, seriously threatened by the economic rise of Germany, a country rapidly becoming industrial top heavy and feeling ever more sharply the need for markets.
Langer faults the policy of both nations for the peculiar difficulties in which they would eventually find themselves. The British hated the idea of making extensive concessions to the Germans, while the Germans always felt that the British, already the possessors of a large part of the globe, begrudged their late blooming cousins even the most trivial acquisitions. The famous Kruger telegram one of the greatest blunders of modern diplomacy brought to the surface all the jealousy, distrust, and ill feeling that had been gradually accumulated between the two nations. It reflected in part the perverseness of various strains of German policy, which, on the one hand, sought to frighten the English into closer relations with the Triple Alliance; and on the other, to create a political-economic combination of continental powers to combat the growing British friendship with the United States. Such a continental coalition against England would create a naval combination that the Royal Navy could not hope to combat on equal terms. Short of that, there was Tirpitz’s idea that Germany might itself build enough ships as to position itself to tip the naval balance against Britain, which would cause London to become more accommodating. In this climate, the teachings of the American naval writer, Alfred Thayer Mahan, found willing audiences, as Langer amply documents.
Of course, there was more than a little hysteria in this rampant imperialism and much sleep was lost over territories of no importance. But these psychological elements, especially acute in the growing Anglo-German rivalry, must be considered. People simply became panicky as they saw the world shrinking. Nothing seemed quite as important as to get everything possible before it was too late, and to allow as little as possible to pass into the hands of competitors. The Germans made something of a nuisance of themselves by interjecting themselves into every problem and demanding compensation everywhere and at all times. But it is equally true that the Britain took a negative stand to begin with and showed an extraordinary tendency to look with greater equanimity upon the various appetites of Russia and France than upon the relatively unimpressive nibbling of the Germans. The only explanation is that the Russians and French were not considered serious commercial rivals of the British. They were not getting the better of the British even in the markets of the empire, as were the Germans. It was that which lay at the bottom of Britain’s suspicion and jealousy. This part of the Anglo-German antagonism did decline over time but the barriers to some sort of comprehensive understanding had been raised once European politics later came to the fore.
The shifting European alignments, and particularly the growing Anglo-German tensions and efforts to resolve that relationship, became entangled with the Far Eastern problem (as it was then described). According to Langer, when the two aspects are put together, it will appear unmistakably that the real object of English policy throughout these years chiefly because of critical developments in the Far East was to reach an agreement with Russia. Japanese statesmen, in turn, also wanted an agreement with Russia, and it was the failure of both England and Japan to come to such an agreement that brought them rather reluctantly together. (The Anglo-Russian rapprochement would have to wait, until the latter’s defeat in the Russo-Japanese War of 1904-1905 forced the government in St. Petersburg to undertake a fundamental rethinking of security policy).
The construction of the Trans-Siberian Railway was regarded throughout the world as a portentous departure from Russian policy; as an event bound to transform the whole of the Far Eastern and imperial question and at the same time modify the whole framework of international relations. Japan as well as China watched the plan with deep apprehension. In Tokyo it was feared that if the Russians completed their system of communications it would no longer be possible to resist their advance with anything like even chances of success. Yet the independence of Korea or its ultimate control by Japan was looked upon as indispensible to the security of the Empire. This judgment led to Japan’s war with China. When the Chinese were routed (but the Japanese were frustrated in the subsequent diplomatic settlement), there was an inevitable reordering not only of the Far East with the appearance of a new great power, but of European security, as well.
— Patrick J. Garrity, October 19, 2010