September 11th 2001 was the day the world changed.
That journalistic truism will be endlessly repeated this week in the wake of the death of Osama bin Laden, which was dramatically announced by President Obama last night. The killing of Bin Laden, some 3520 days after Al Qaeda's terrorist attacks on New York on Washington, will now symbolise closure for many people on those terrible and shocking events.
It is naturally the role and responsibility of governments to stress a potentially heightened level of threat, in the next few days and weeks. Yet, at a stroke, this Autumn's retrospectives on the 10th anniversary of 9/11 will now become ever more an exercise in contemporary history, rather than current affairs. The focus of most will be on the human stories of tragedy and heroism. The political protagonists - Osama bin Laden, as well as Bush, Cheney, Giuliani, Blair et al - now belong to the history books, their actions and reputations to be picked over and reassessed along with the Kennedys, Reagan, Thatcher, Gorbachev and the rest.
Yet perhaps bin Laden's death can bring a sense of closure partly because, a decade later, 9/11 changed the world rather less than we intuitively think that it did. That seems a strange thing to claim after a decade in which the content and atmosphere of international and domestic politics were often dominated by the attack on the twin towers and the reaction to them. But what if we ask the 'what if?' question, and try to gauge the shape of our world if 9/11 had never happened? The geopolitical and public mood of the last ten years would have been dramatically different. Yet the forces doing most to reshape our world now - the global shift in power eastwards to China and India, the consequences of the financial crash of 2008, and the shifting demographics of western societies - were little affected by the disruptive impact of 9/11, and their impacts seem likely to long outlast it.
With a decade's hindsight, one of the most striking things about the 9/11 attacks was that they were not only the first successful foreign [terrorist] attack on US soil but also - to date; fingers crossed - the last too. The subsequent failure of Al Qaeda partly reflected the disruption of the network, scattering its Afghan base to the winds after 9/11. But the 9/11 attacks were preventable too. One doesn't need to subscribe one iota of conspiracy theory to believe that. The terrorists required a lot of luck. They could have been apprehended - they nearly were - at a Boston airfield, taking flying lessons, in August.
Al Qaeda existed before 9/11, of course. Bin Laden was on the CIA 'most wanted' list. But killing many hundreds in Nairobi and Dar Es Salaam, even by bombing American Embassies in Africa, did not move him too often from the foreign news pages. Bin Laden was known to governments and security services, to specialist journalists and academics, and to those seeking to promote his twisted idea of 'jihad' to attract young Muslims. But most citizens in western democracies, and most Muslims around the world too, would not have heard his name until after 9/11.
The global notoreity achieved by that global PR 'spectacular' was essential to seek to promote the widespread fear and polarisation that was essential to bin Laden's cause. In this, bin Laden achieved some success in the years after 9/11, though surely rather less than he would have anticipated, or indeed needed.
If 9/11 had been prevented, certainly much would have been different in the short-term. It shaped the international politics of a decade, but it no longer looks as transformative as 1917, 1945 or 1989.
It is unlikely there would have been any concerted international effort to loosen the grip of the Taliban/Al Qaeda alliance in Afghanistan, despite long-standing UN resolutions denying legitimacy to the regime. Al Qaeda itself would have not had the need nor notoreity to catalyse its shift so quickly from organisation to 'brand', where followers might attempt to emulate the achievements of bin Laden, without central direction or control.
Al Qaeda, or its allies or emulators at least, did strike in Madrid in 2003 and London in 2005. These attacks may still have happened if 9/11 had not. Or not. But much might have been different in Transatlantic approaches had there been an attack in Europe, and not in the United States. Instead of debating Robert Kagan's theory about Americans being from Mars and Europeans from Venus, the issue may have remained concerns about US withdrawal and isolationism (a debate, it is usually forgotten, that was prominent around Bush's election in 2000).
US domestic politics did change too. On the day of 9/11, the question of the legitimacy of George W Bush's being installed as President by the Supreme Court simply ended. Without it, the consequences of the knife-edge election in which Al Gore had won more votes but lost the electoral college amidst hanging chads would have reverberated through his term. Gore may have replaced John Kerry to have a second crack at the Presidency. Perhaps the outcome would have been similar, though with Bush not running on a 'War President' ticket, it is harder to construct the content of the campaign. Who knows whether we would ever have heard of the talented Illinois politician Barack Obama?
In Britain, we would have found out what Tony Blair's second term might have been about if 9/11 had not happened three months into it. He was, on the morning of September 11th, about to give a defining speech about Britain and Europe to the TUC conference. Having secured a second landslide made Blair a dominant domestic political personality - except that tensions with his Chancellor Gordon Brown were bound to come to the fore once Blair had been re-elected. But it was 9/11 that gave Blair a global profile far beyond that of his leading role over the Kosovo war or debates about modernising the EU.
What really changed the geopolitical scene was less the Afghanistan war - which had extremely broad international support, and was unimpeachable in international law- but than the war with Iraq.
So, was the Iraq war a consequence of 9/11? Any assessment of the "impact of 9/11" probably hinges on this question. It is difficult to say. It is at least arguable that, on balance, it was not.
Those in Washington, like Dick Cheney, who had always been keen to return to the question of Saddam did certainly use the changed atmosphere to put Iraq back in their sights.
Yet there was, of course, no link between Al Qaeda and Saddam - though it was the arrival of US troops on Saudi soil for the first Gulf War which bin Laden chose as his casus belli. So the issue of Saddam Hussein, his willingness to accept the terms of defeat in 1990, and US claims about his WMD programme, were in play without bin Laden. My strong hunch is that the Bush administration would have found a route to Baghdad, though they may have needed to secure a second term to do that, perhaps closer to 2005 rather than 2003.
If that is the case, then perhaps much of the history that has become familiar to us, the confrontation with Saddam and the missing WMD, the impact of the Bush-Blair alliance, Europe divided, and the rise of Obama would indeed occur anyway.
But it would not then have taken the terrorism of Osama bin Laden to provoke it.
This is not to argue that Osama bin Laden didn't matter. Tragically, he did - and not just for those directly affected by attacks he inspired or organised in America, Britain, Spain, Bali, Kenya, Tanzania and elsewhere.
Citizens of the west have had good reason to fear our societies becoming more fractured, as extremist Islamist and white far right minorities put effort into mutually stoking and fuelling each other's fears and grievances, despite the evidence that a strong majority of Muslim citizens clearly reject Islamist extremism, and some effective efforts - notably after the July 2005 attacks on London - to articulate the common ground that most of us share.
We have had a sharp public debate too about when and whether we need to restrict our freedoms in order to protect them. These issues are often considerably more difficult than some of those who criticise governments tend to admit. Yet governments have certainly over-reacted - most seriously at Guantanemo Bay; most absurdly in petty restrictions on political protest which have nothing to do with any security threat. But the vigilant and sharp public contest over these issues may yet prove a reason to be hopeful about striking a better balance too, as the current Coalition government says that it intends to do.
So Bin Laden failed too. Certainly, in the west, the politics of bin Ladenism always remained an extremely small extremist fringe in political terms, though a couple of thousand adherents can present a dangerous security threat. One of the many reasons to take hope from the Arab Spring is that the protests ultimately increase the possibility of bin Laden's Islamist extremism being marginalised across the Middle East too, as popular grievances take a genuinely democratic form.
Nobody ever did more to promote a 'clash of civilisations' between the Islamic world and the west. So we can secure bin Laden's failure if we can indeed demonstrate that his vision of fear and conflict is further away from being realised in 2011 than it was in September 2001.