How has a constitutional lawyer and mid-level political staffer, admittedly rather bright, pulled this off? Part of it is timing. "The shield of Achilles" is grand history as polemic, making it a rarity in the post-Toynbee era, when professional historians write annotated chronicles or highly focussed case studies. This retreat into scholasticism has left a void on the politician's bedside table that memoirs and theory cannot satisfactorily fill, at a time when the defeat of the Soviet Union has left the West without clear purpose. Bobbitt's book has been seen (wrongly) as anticipating the September 11 atrocities. And as a revised and expanded lecture course, it comes in bitesize modules and in easy prose suited to busy elites lacking specialist knowledge.

So what does "The shield of Achilles" actually say? A lot. Bobbitt strikes a sound balance between concision and exposition, which given the length of the book allows him first-class legroom. The book's six parts, three on war and three on peace, are interdependent, but the historical sections are props for an explicit attempt to construct plausible future scenarios based on alternative present-day choices. In each modern historical era, Bobbitt identifies competing constitutional orders defined by strategic innovations and differing bases for legitimacy. These forms clash in epochal wars, which bookend eras, and the victorious constitutional order reifies its triumph in a peace treaty. The triumphant constitutional order then dissolves in diversity, seeding divergent forms that will compete for legitimacy in the succeeding era. The old century is unusual only in that the 1914-1989 period was one long epocal war. The clash between the fascistic, communist and parliamentary forms of the nation-state was resolved by the Peace of Paris in 1990. Our impression that the power is simultaneously slipping away from and accruing to the State is quite correct, since the nation state (deriving legitimacy from a promise to better the welfare of the nation) is giving way to the market-state, whose maxim is to maximise opportunity. Entrepeneurial, managerial and mercantile descendants of the parliamentary state, loosely corresponding to the United States, European Union, and Japan, are emerging, and a war between them "is part of the natural condition of the State."

Bobbitt accords surprisingly little power to non-state agencies, such as corporations, multilateral institutions, and terrorist groups. Since constitutional orders can only be encoded in the internal structure of great powers, great-power relations determine the course of history. This is an imperial - Kissingerian - view of the world, and Bobbitt plays down the importance of rogue states and rebellions. He quips that while the classic problem of the nation-state was to distinguish the terrorist from the freedom fighter, the market state's defining dilemma will be to distinguish the businessman from the criminal. Bobbitt's world has moved on, but the real world hasn't. Although much of the stain of the mid-1990s (the lectures were written between 1992 and 1997) has been removed from the text, it survives in aphorisms, giving the book an anachronistic taste.

Just as you start to take issue with one of Bobbitt's assessments, he jumps ahead. Almost any example will serve, but given his deep background in deterrence theory, his seven pages on nuclear proliferation are shockingly trite. The keystone is an approving quote from the apostle of future war, Martin van Creveld: -

There seems to be no factual basis for the claims that regional leaders do not understand the nature and implications of nuclear weapons; or that their attitudes to those weapons are governed by some peculiar cultural biases that make them incapable of rational thought; or that they are more adventurous or less responsible in handling them than anyone else.

This is absurd. Even the most cursory study of the acquisition of nuclear weapons by France, China, India, and North Korea, or the divestment of South Africa, Kazakhstan, Belarus and the Ukraine, shows the overriding importance of local politics. Small polities are not rational actors. The only states that followed the threadbare and deterministic course assumed universal by Bobbitt were the Soviet Union, Pakistan and the Argentina/Brazil pair, and outside pressure prevented that last from reaching the weapons-ready stage.

But picking at the thread of "The shield of Achilles" is unfair. As a lecturer, Bobbitt's aim is to provoke and inspire. His brevity avoids the prolix deadliness of most popular writing on world policy. By contrast, "The shield of Achilles" is dense with ideas, and bears re-reading. The framework for events that Bobbitt proposes - the emergence of the market-state from the ruin of the nation-state - is probably valid, and this alone is a major contribution to world policy.

This wide-ranging and exhaustive book has crucial things to say about not only the history of the State, but also its future in the 21st century: along with countless, highly readable examples of war, peace, diplomacy and state-building spanning hundreds of years of history (and countless theoretical formulations extruded from these examples), Bobbitt gifts the reader with visions (plural, for he does not stop at one dystopia) of our possible future all the more chilling for their intricately calculated logic. His crisp, clear prose ensures accessibility, and no reader will be left either underwhelmed or unengaged. This thoroughly enjoyable, deeply enriching book is an essential read - definitely not to be missed, or ignored.