10 years on: my thoughts on 9/11
I can't remember exactly when, on September 11, 2001, I first heard the words: "The world has changed for ever." But it was very soon after the attacks in New York and Washington, and I remember feeling sceptical: I have a deeply engrained distrust of such sweeping generalisations.
On that occasion, though, I was probably wrong to be sceptical. For many millions of people - in the US, of course, but also in Europe, in the Middle East, and in Afghanistan - the world did change as a result of what happened that day.
So what have we learned over the past decade?
First, that we understand far less than we should about what is going on in faraway places - and that we ignore them at our peril. Before 9/11, had you heard of al-Qaeda, or Osama bin Laden? How much did you know of what was happening in Afghanistan, or Pakistan, or Saudi Arabia?
Second, that military might - even US military might - does not solve problems as easily as we might like to imagine. The Gulf War of 1991, after Saddam Hussein invaded Kuwait, was an anomaly: an easy victory that achieved its stated aim at relatively low cost.
Third, that "temporary" anti-terrorism measures have a funny habit of becoming permanent - as any air traveller has discovered.
Fourth, that we can learn to live with fear. Just as Londoners did during the IRA bombing campaigns of the 1970s, now New Yorkers, Madrileños, Parisians, residents of Mumbai and Delhi, Karachi and Islamabad, Kabul and Kandahar, have discovered that you can get on with your life even in the knowledge that a bomb may be about to explode at any moment.
It's true that since 9/11 - with the exception of the attacks at the Fort Hood military base in Texas in 2009 when 13 people were shot dead, allegedly by a Muslim American serviceman - there have been no further attacks in the US. But there have been several unsuccessful attempts, including by the so-called "underpants bomber", Umar Farouk Abdulmutallab, who allegedly tried to blow up a plane on its way to Detroit in December 2009, and the attempted bomb attack on Times Square in New York in May last year.
(Last night, US officials said they had received "specific, credible but unconfirmed threat information" relating to the anniversary of the 9/11 attacks this weekend. It was reported that at least three people - one believed to be a U.S. citizen - had flown to the U.S. last month, apparently from Afghanistan, planning to set off a car bomb.)
Ever since 9/11, Muslims living in non-Muslim countries have found themselves being regarded with suspicion and incomprehension. Islamophobia is just one of the new, and unlovely, words we have learnt, along with Guantanamo, Abu Ghraib, extraordinary rendition, waterboarding, control orders, and assymetric warfare.
But perhaps there are dangers if we focus too much on 9/11: that we try to relate everything that has happened over the past decade to what happened on that terrible day - and that we fail to acknowledge the other profound changes that have been under way while we've been concentrating on potential suicide bombers.
As the former Foreign Secretary David Miliband pointed out in an article this week, over the past 10 years, the combined GDP of Brazil, Russia, India, and China more than doubled, from 8.4 per cent of the global economy to 18.3 per cent.
It was also the decade when, in his words, internet access went global - from a third of a billion people in 2000 to more than two billion people today. And the US started to realise that it is no longer the undisputed global super-power that it once was.
I wouldn't be at all surprised if historians, when they look back on this first decade of the 21st century, devote at least as much space to those developments as to the aftermath of the attack on the Twin Towers.
Terrorism is sometimes described as the weapon of choice for those who have no other weapons. And perhaps the best news in this grim 10th anniversary year is that tens of thousands of young Arabs who a decade ago may well have felt they had no other weapons with which to press their demands have now discovered the power of mass street protest.
Over the past eight months, in Tunisia, Egypt, Syria, Yemen and Bahrain (Libya, where they quickly took up arms, is in a slightly different category), angry and ignored young people have turned their backs on the nihilism of al-Qaeda ideology and have decided instead to confront their own leaders on their own streets. Their demands for democracy, freedom and choice couldn't be further from the vision of Osama bin Laden.
It doesn't mean that the threat of more terrorist attacks has gone away, and we still don't know whether their protests will eventually succeed - after all, overthrowing a hated dictator is not the same as building a better future - but at least they're not blowing up themselves, or us. For that, surely, we can be thankful.