World-political reflections in historical perspective—as distinct from liberal-normative self-congratulations—have been a rarity in postwar federal Germany. Even the short-lived post-reunification hubris that incited secessions in Slovenia and Croatia failed to hasten a resumption and updating of the rich and disturbing Prusso-German discourse of Machtpolitik in academia and policy circles. The discursive hegemony of the ‘power of the better argument’, and its Genscherite geopolitical pendant of Atlanticist multilateralism and chequebook foreign policy, remained too entrenched. To all appearances, the Luftwaffe’s reappearance in Balkan skies, wing-tip to wing-tip with nato allies in the bombing of Yugoslavia, merely uncorked another round of Kantian celebrations. A threshold, nevertheless, had been crossed. Three years into the war in Iraq, publicly deplored but clandestinely assisted by Schroeder and Fischer, Herfried Münkler’s Imperien has broken self-imposed taboos by bracketing—naturally, without repudiating—ethical considerations, for a comparative enquiry into the transhistorical ‘logic of empire’, with gratifying sales and critical reception in the Federal Republic.

Emblematic of intellectual and political mutations under way in the Germany of the turning century, its author began his career in left-leaning milieux at Frankfurt University in the 1970s and 1980s. By background a historian of ideas, he was a student, assistant and collaborator of Iring Fetscher, the author of several studies on socialism and editor of anthologies of Marx; in due course Münkler himself became a long-time member of the editorial board of mega , the projected 114-volume Marx-Engels-Gesamtausgabe. A dissertation on Machiavelli led to a Habilitationsschrift on the rise of the idea of raison d’État in early modern Europe, and thence to a co-edited five-volume history of political ideas, preoccupations with Clausewitz and Schmitt, and eventually towards a military sociology of war, terrorism and partisan warfare. An editor for many years of the Politische Vierteljahresschrift, the country’s leading political science journal, Münkler now adorns the Berlin-Brandenburg Academy of Science, and holds the Chair for Political Theory at the Humboldt University in Berlin, a position to which he was appointed in 1992 after the political purges of hold-outs from the old regime at this former East German flagship university. Once a commentator in Tageszeitung—Berlin’s nearest equivalent to a radical, counter-cultural left daily, however invertebrate—today he is lauded by Die Zeit and regaled by the German Foreign Office, to whose Ambassadors’ Conference Imperien was originally presented in 2004 as an aide-mémoire.

Designed as a comparative historical sociology of empires, Imperien seeks to distil the essential characteristics and dynamics of empire as an ideal-typical concept, with a view to clarifying current American projects and necessary European responses to them. Though compact in extent, the book is vast in scope, ranging from nomadic empires of the Central Asian steppes, via the Hochkulturen, to the Greek, Persian, Roman and Chinese imperial orders and on to Ottoman, Portuguese, Dutch, Spanish, French, Russian, British and Soviet successors. Declaratively, Münkler’s interest lies not so much in drawing lessons from this array of past experiences, as in identifying regularities across the historical spectrum that work themselves out largely independent of the volition of their protagonists. ‘Political physics’ not ‘political prudence’ is to hold centre stage. The ‘imperatives’ rather than the ‘politics’ of empire are what matters. ‘An approach that inquires into the logic of empire and its imperatives of action attributes minor significance to the influence and decisions of actors. It rather seeks to identify those structures and premises that define their room for manoeuvre’.

What are then, for Münkler, the essential components of empires? If states are classically defined by sovereignty, bordered territoriality and homogeneous internal integration, generating reciprocal and (in principle) juridically equal international relations, empires are not simply larger versions of them—magnified, but comparably demarcated, units in a geopolitical pluriverse. They are something quite distinct: systems of rule surrounded by political communities (clients or satellites) of lesser and dependent status, open to constant intervention and direct and indirect political management. Within such empires, too, there is always an internal gradient of uneven and decreasing administrative and legal integration between centre and periphery, with semi-porous and shifting frontier-zones that tend to let out but only selectively let in. No grand strategy is discernible during their initial formation—Seeley’s conceit that the British Empire was founded ‘in a fit of absence of mind’ is generalized with gusto. Imperial dynamics are not reducible to the impact of the centre on the periphery, but co-determined by interactions between the two. If military might and economic power are the mainstay of empires, they also require a legitimating discourse that holds out the prospect of attraction into the imperial fold—eternal peace, prosperity, civilization, free markets, democracy-promotion, human rights. This mission constitutes a self-binding discourse, rather than an ideology in the classical sense; it is neither a set of conscious fabrications nor a form of self-delusion, but a normative pledge that at once restrains imperial rule and relegates those who oppose it to barbarity. If power of attraction fails, a just war can be proclaimed that criminalizes the enemy by imposing a new international legal order—iustus hostis becomes a rogue state. Internally, the mission rallies the metropolitan population by rationalizing and legitimizing fiscal and military sacrifices.

True empires, Münkler insists, if they want to be Weltreiche and not mere Großreiche, require not only an imposing expansion in space but also a substantial duration over time. Crucially, they need to be capable of trans-generational regeneration after an initial phase of charismatic take-off has exhausted itself. On this count—conveniently, of course, for current purposes—the Napoleonic, Bismarckian and Nazi (even, more perversely, Japanese) ventures drop out of the picture. Indeed, real empires need to have passed through at least one cycle of rise and decline, plus a renewed period of ascent. Spatially, empires tend to be co-extensive with their ‘worlds’ in the sense that imperial co-existence and co-recognition is a contradiction in terms, leading inescapably to inter-imperial conflict. Exception is made for those cases where ‘parallel empires’ co-exist, but failed to interact due to their mutual geographical isolation, as in the case of Imperial Rome and Han China. The historical trend line, in any case, leads to a spatial congruence between a single empire and the globe (henceforward including outer space), even though the move towards informal empire imparts a transglobal, rather than a global, character to the American project. While Münkler notionally allows for hegemony as a possible third category, defined as predominance over a group of formally equal actors in which the hegemon assumes the position of primus inter pares, in practice his essential classification of political communities is exhausted by a fundamental state-empire dualism.

What are the distinct imperatives of imperial rule? Within their sphere of domination, empires are compelled to political or military intervention to maintain their credibility, prestige and, ultimately, power and influence. Here neutrality is not an option: Thucydides’s Melian Dialogue sets out the reasons why satellites must be kept engaged in and subordinated to the common imperial project. Melos could not stay out of Athens’s conflict with Sparta; in more recent idiom, ‘who is not for us is against us’. For their part, inter-imperial relations are governed by permanent geopolitical competition over relative standing, a drive towards hierarchization grounded in the demands of power politics and manifested in a series of asymmetric—typically proxy—wars, conducted against minor peripheral powers. These signal prestige and strike-capacity to imperial rivals. Ultimately, inter-imperial hegemonic wars decide the fate of the world order.

If the theoretical construction so far offers a quasi-realist account of geopolitical force fields, in a central chapter Münkler returns to the domestic politics that govern the trajectory of empires. Here, after evoking Polybius’s and Machiavelli’s political cycles, Münkler appeals to Michael Mann’s four sources of power (ideological, economic, military and political) and Michael Doyle’s notion of an ‘Augustan threshold’, to reject either economistic or uni-cyclical models of imperial ascent and descent, for multi-factor and pluri-cyclical explanations of the variable rhythms of rise and decline. Of the latter two theoretical crutches, more is made of the second than the first. In Doyle’s version, the Augustan moment signifies a series of fundamental constitutional and moral reforms—in Rome, Octavian’s sealing of the transition from de-centralized republicanism to re-centralized authoritarian rule—in which empires terminate their phases of military expansion and enter long periods of socio-political consolidation and imperial order.