More often quoted - and pilloried - than read, Fukuyama's essay and subsequent 1992 book captured and stoked the triumphalism that followed the end of the cold war. Incomes rose. Technology progressed. Mikhail Gorbachev did a Pizza Hut commercial. Rhetoric about the inevitability of freedom only seemed to intensify after attacks on Western supremacy in the 21st century.

In many ways, it all suggested he was right. The blandness of today's academic and political debate proves Fukuyama's contention that it no longer seems possible to think of theoretical alternatives to market capitalism. It's easy to make fun of Fukuyama, Slavoj Zizek wrote, but most of us are now Fukuyamaists.

But is Fukuyama? A mood remindful of the happy 1990s has been observable recently. Uprisings in the Arab world and, less recently, Iran have produced a similar sense of inevitability and optimism. Fukuyama has not been taken in: 'I think people are going to be disappointed,' he says. 'I don't think it's going to lead to a stable democracy from any short-term perspective. Institutions don't come about overnight. They have to be built over time; this is something that people in the Arab world are going to experience. In some of the states that have less sense of nation, you could get sectarian war'.

In The Origins of Political Order, Fukuyama examines the many paths humans took to developing a cohesive sense of nation and stable states, and how they came unstuck. It's an ambitious and brilliant work; the first of a two-part opus.

He was inspired to take on the subject after his research into state failure in Afghanistan made him consider the conditions required for statehood. Fukuyama also found himself dissatisfied with anthropology and cultural studies, their 'anti-Western narrative' and reluctance to compare societies 'effectively or honestly'. The book draws attention to the conditions that promoted the development of human political institutions from bands of hunter gatherers to modern bureaucracies. He draws on biology, archaeology, anthropology, economics and history in a narrative that spans pre-human history to the French Revolution.

Africa's vast plains go some way to explaining its lack of political institutions. Tribes could flee from oppressors without any geographic impediments. Had they been bound to territory by mountains or other geographic features, tribes could have continued to absorb other tribes in the process of violent conquest and consolidation necessary for state formation. In Afghanistan the opposite conditions had the same effect. The region's mountainous divisions and low population density made it impossible for any one tribal society to travel across enough territory to control significant populations.

Fukuyama is at pains to avoid drawing any general conclusions or unifying narrative. In many ways, the book reads like an antidote to his first. Where Fukuyama once portrayed it as marching to an intelligible logic, the political scientist now seems more aware of the random events and missteps that make up history.

When asked, Fukuyama still holds to his original theory, but concedes a change in perspective and emphasis: 'I hope this most recent book is able to show how accidental and contingent a lot of Western history was.'

If there is a recurring theme to his book it is humankind's ceaseless struggle to build modern and accountable institutions in the face of ineradicable human desires to do favours for friends and family. His book is littered with examples of societies that have developed ingenious means of overcoming corruption, only to relapse.

'One thing that I emphasise in the current book that was not in the original one was the possibility of political decay. Democracy, no less than any other type of political order, can get rigid and fail to adapt over time.'

Fukuyama says there is an alternative to liberal democracy in ascendant, undemocratic China. In his original essay, Fukuyama predicted that the decline of China's political system would be hastened by the rise of its economy. Now he concedes authoritarianism has its advantages. 'They can do this in a certain sense because they are authoritarian. They don't have checks and balances to prevent a state like India dealing with infrastructure and investment problems and the like.'

Fukuyama was, until recently, a hardcore neo-conservative. He was a foundation member of the Project for the New American Century, a think tank that agitated for the promotion of American leadership and interests through a combination of 'military strength and moral clarity'. Fukuyama a signatory to its 1998 letter calling for the invasion of Iraq, a document widely credited as the genesis of the 2003 invasion by the US.

He says he supported the invasions of Iraq and, later, Afghanistan, on security grounds, but became sceptical once the justification for the war veered towards exporting democracy and nation-building: 'I think if they remembered the early tradition, they would not have tried to do this kind of social engineering in Iraq.' The depth of his thinking and proclivity for abstraction make it hard to determine how much Fukuyama has changed his mind. He is overly concerned with presenting himself as entirely consistent. But he seems like a man himself propelled by the clash of ideas and internal contradictions.

So does Fukuyama have a newfound appreciation for the many directions history can move? Or is it, as he says, just a matter of emphasis? Fukuyama insists - inadvertently, of course - that five years ago he was still acting the part of the optimist on democracy in the Arab world about which he was so circumspect earlier.

Earlier this year it was revealed that Fukuyama was one of many US academics associated with the Monitor Group, a consulting firm launched by professors from Harvard's business school. Monitor won a US$3 million contract to help burnish the Libyan regime's international image and the money was used to finance trips and consultancy fees for a range of US academics to meet Muammar Gaddafi and members of his regime.

Does the man who argues that democracy is the highest form of human evolution see any contradiction in taking money from a dictator? 'Had I known the way things would turn out, I wouldn't have done it,' he says.