The horrific thing about Osama bin Laden was that he helped to kill thousands of innocent people throughout the world. But he was also in a strange way a godsend to the west. He simplified the world. When communism collapsed in 1989, the big story that had been hardwired into citizens of western countries – that of the global battle against a distant dark and evil force – came to an abrupt end. Understanding the world became much more complicated until, amid the confusion of a global economic crisis in 1998 and the hysterical spectacle of the Monica Lewinsky affair, Bin Laden emerged as the mastermind behind the bombings of embassies in east Africa.

President Clinton immediately seized on it. He fired off cruise missiles, they missed, and everyone accused Clinton of using Bin Laden to take the heat off himself. But if you look back at some of the pieces television reporters did that day in Washington, you can see something else too: the murky shape of an old story slowly re-emerging, like a wreck rising up from the sea.

Illustration: Peter Till

Bin Laden and his ideological mentor, Ayman al-Zawahiri, talked about "the near enemy" and the "far enemy". But from 2001 onwards they became America's "far enemy". Neoconservative politicians, who had last tasted real power under President Reagan during the cold war, took the few known facts about Bin Laden and Zawahiri and fitted them to the template they knew so well: an evil enemy with sleeper cells and "tentacles" throughout the world, whose sole aim was the destruction of western civilisation. Al-Qaida became the new Soviet Union, and in the process Bin Laden became a demonic, terrifyingly powerful figure brooding in a cave while he controlled and directed the al-Qaida network throughout the world. In this way, a serious but manageable terrorist threat became grossly exaggerated.

Journalists, many of whom also yearned for the simplicity of the old days, grabbed at this: from the outset, the reporting of the Islamist terror threat was distorted to reflect this dominant simplified narrative. And Bin Laden grabbed at it too. As the journalists who actually met him report, he was brilliant at publicity. All three – the neoconservatives, the "terror journalists", and Bin Laden himself – effectively worked together to create a dramatically simple story of looming apocalypse. It wasn't in any way a conspiracy. Each of them had stumbled in their different ways on a simplified fantasy that fitted with their own needs.

The power of this simple story propelled history forward. It allowed the neocons – and their liberal interventionist allies – to set out to try to remake the world and spread democracy. It allowed revolutionary Islamism, which throughout the 1990s had been failing dramatically to get the Arab people to rise up and follow its vision, to regain its authority. And it helped to sell a lot of newspapers.

But because we, and our leaders, retreated into a Manichean fantasy, we understood the new complexities of the real world even less. Which meant that we completely ignored what was really going on in the Arab world.

As journalists and Predator drones searched for the different al-Qaida "brands" across the regions, and America propped up dictators who promised to fight the "terror network", a whole new generation emerged in the Middle East who wanted to get rid of the dictators. The revolutions that this led to came as a complete shock to the west. We have no idea, really, who the revolutionaries are or what, if any, ideologies are driving them. But it is becoming abundantly clear that they have nothing to do with "al-Qaida". Yet ironically they are achieving one of Bin Laden's main goals – to get rid of the "near enemy", dictators such as Hosni Mubarak.

One of the main functions of politicians – and journalists – is to simplify the world for us. But there comes a point when – however much they try – the bits of reality, the fragments of events, won't fit into the old frame.

The death of Bin Laden may be that point for the simplified story of goodies versus baddies. It was a story born in the US and Britain at the end of the second world war – the "good war". It then went deep into the western imagination during the cold war, was reawakened and has been held together over the last 10 years by the odd alliance of American and European politicians, journalists, "terror experts" and revolutionary Islamists all seeking to shore up their authority in a disillusioned age.

Barack Obama seems to be rejecting this story already. The Europeans still cling to it, though, with the return of "liberal interventionism" in Libya, but it is anxious and halfhearted.

But it is in Afghanistan that the story is really falling apart. We are beginning to realise that this simplification has led to completely unreal fantasies about who we are really fighting. Fantasies that only persist because they justify our presence there. For the fundamental problem with this simple story of good versus evil is that it does not permit a proper critical framework that allows you to properly judge not only those you are fighting, but also your allies.

America and the coalition invaded Afghanistan with the simple aim of destroying the terror camps and setting up a democracy that would allow the country to be ruled by good people. But in the ensuing decade they have been tricked, spun round and deceived by the complex web of vested interests there. And their inability to understand and deal with this has led to the rise of a state crippled by corruption in which it is impossible to know who the "good" people might be any longer.

Meanwhile President Harmid Karzai has immediately pointed out that Bin Laden's killing proves that the real terrorist threat is in Pakistan – and the fight against terror in his country is a fantasy. But we also know that much of what Karzai says may also be the fantasies he uses to justify the growing power of the small elite around him. And so Afghanistan becomes a hall of mirrors – except the one thing everyone agreed on was that Bin Laden wasn't there.

With Bin Laden's death maybe the spell is broken. It does feel that we are at the end of a way of looking at the world that makes no real sense any longer. But the big question is where will the next story come from? And who will be the next baddie? The truth is that the stories are always constructed by those who have the power. Maybe the next big story won't come from America. Or possibly the idea that America's power is declining is actually the new simplistic fantasy of our age.