Rupert Cornwell: So this is history?

Even three-and-a-half months later, the monstrous attacks of 11 September still seem more like virtual reality than events in the actual world capable of human comprehension. Most of us are still in some kind of shock – and still wondering, in the headline writers' hyperbole, if the world will ever really be the same again.

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The shadow of terror: Three months on

Even three-and-a-half months later, the monstrous attacks of 11 September still seem more like virtual reality than events in the actual world capable of human comprehension. Most of us are still in some kind of shock – and still wondering, in the headline writers' hyperbole, if the world will ever really be the same again.

But shock and spectacle are not necessarily the measure of significance. Unspeakable things happened on 11 September – but did they mark a turning point in history? As we attempt to explain these events, we turn to the past for clues. Was this another Pearl Harbor, the last comparably deadly foreign attack on American soil, which pulled the US into the Second World War? Or a 21st-century equivalent of the assassination of Archduke Franz Ferdinand in Sarajevo in 1914, setting off what some commentators proclaim to be the Third World War? Or was it a new sort of war, not within states or between states, but what Samuel Huntingdon predicted would be the coming "clash of civilisations"?

The truth, I think, is more mundane. The deadliest single terrorist atrocity in modern history was a calamity waiting to happen. But it was not, except in its scale, unprecedented.

Almost nothing about the attacks was new: neither the ingredients nor even the technique employed. Middle Eastern terror has stalked the US for decades: it was back in 1983 that terrorists drove a truck full of explosives into a barracks in Beirut, killing 240 US Marines. A decade later, the World Trade Centre was itself a target for the first time. There had been earlier attempts, happily thwarted, to turn commercial airliners into giant kamikaze jets.

Nor is hatred of American dominance and resentment of American arrogance anything new: "Yanqui go home", "the Ugly American" – phrases like these have been around for half a century. Even the economic downturn that is causing so much pain now had begun six months before the attacks. What was new was the ambition and the co-ordination of the operation, and the targets chosen – not exposed targets abroad, but the symbols par excellence of America's military and economic might, on America's own soil.

In its direct impact on history, 11 September is unlikely to match Pearl Harbor. That was a truly pivotal event. It provoked the entry of the US into the Second World War and thus sealed that conflict's outcome. The elements that now seem to define the post-11 September world – failed states, radical Islamic terrorism, the mess in the Middle East, recession – were all present beforehand. The attacks merely gave history a big shove down a path along which it was already proceeding. Nonetheless, it is understandable if we ask ourselves with more urgency than before: where was that path leading?

The first notion to be disposed of is that 11 September somehow portends a shift in the global balance of power. This was no Manzikert – the battle in which the Muslim Seljuk Turks defeated the emperor Romanus IV Diogenes in 1071, dooming the Byzantine empire to its eventual collapse. A better comparison, in the light of events in Afghanistan, might be the fall of Khartoum in 1885 to the Mahdi, an earlier proponent of Islamic uprising against an outside imperial power. That defeat was swiftly avenged by the British empire, the premier global power of the day.

The jets that sliced into lower Manhattan's symbols of American commercial and financial power were a terrible scream of frustration, resentment and despair from a culture that has failed to come to terms with the modern world. It detests America's military presence in Islam's Middle Eastern birthplace. It cannot abide America's backing of Israel, and feels helpless before the juggernaut of American popular culture. But Muslim Arab societies cannot create jobs for their young people, still less a political system in which they can express themselves. Therein lies the attraction of the radical solutions proposed by Osama bin Laden, and the huge stockpile of hatred that lay behind 11 September.

The world will flock to a winner, gloated bin Laden on that infamous "smoking gun" videotape. But to any rational observer he is now a loser, guilty of a colossal misreading of the foe that has led to a devastating defeat.

Those who planned the attacks surely expected America to respond much as it had to the 1998 suicide bombings of the two US embassies in Africa: outrage, a few salvoes of cruise missiles, a week or two of bombing, and then back to business as usual. If anything, the evidence of the tape, where bin Laden expresses surprise that the planes did so much damage, supports this theory. He surely would never have sanctioned the attacks had he known the consequences: a full-scale war that routed the regime sheltering him, rolled up large parts of his al-Qa'ida network and left many of his top commanders dead.

Yes, America has been transformed, just as it was transformed by Pearl Harbor. Once again a sneak attack, this time on the US mainland, has shattered an illusion of inviolability. The outrage perhaps even exceeds the anger felt in December 1941. Ultimately, however, what happened that autumn morning marks the moment in which America lost not its innocence, but its naivety. A country that never stops congratulating itself on the superiority of its ways suddenly realised that not everyone felt the same way.

For many historians, the closest parallel to 11 September and its aftermath is not Pearl Harbor but the war waged by the third President, Thomas Jefferson, against the Barbary pirates. The pirates seized American merchant shipping and kidnapped the crews for ransom, all in the name of a holy war conducted from bases in compliant Islamic states. Today's Afghanistan, Yemen and Somalia were early-19th-century Algeria, Tunisia and Libya, then nominally part of the Ottoman Empire.

Eventually the US got fed up and sent in the Marines, who stormed Tripoli in 1805. Today's Marines have moved into the Taliban's old stronghold of Kandahar. And the analogy has a sting in its tail. Despite the loss of Tripoli, other Barbary pirates continued to plunder American vessels until 1816. Now, as then, whatever the outcome in Afghanistan, the struggle to eradicate Islamic terrorism is likely to be long. And today's terrorists have deadlier weapons at their disposal.

Likewise, if 11 September was a declaration of war, it instigated a new kind of war, a conflict in which the opponent is not a state, but a movement reaching across national borders. This is the first true "globalisation war", in which the attackers struck back against the global hegemon they hate. They turned that hegemon's tools of globalisation – commercial airliners, international bank transfers and instantaneous electronic communications that flashed their deed live into living rooms from Botswana to Birmingham and Boston – into weapons against it.

But 11 September did not change the global balance of power. It merely marked the end of a decade of boom, frivolity, complacency and self-deception. Contrary to some predictions, history did not end with the collapse of communism, but as usual moved onward in fits and starts we do not always notice. The attacks did not make the world a more dangerous place. They made the world realise how dangerous it already was.

It could get a lot more dangerous. A strong argument can be made that autumn's most ominous event was not the bombing of the twin towers, but the bizarre, still unexplained anthrax scare in the US. True, only five people died. But the episode was a foretaste of what could happen if terrorists get hold of a weapon of mass destruction – as, sooner or later, they surely will. Within 10 years or sooner, we will probably see a nuclear or biological terrorist attack with the potential to dwarf 11 September for loss of life. In that respect, a new historical chapter has indeed begun.

"All my beautiful lovely safe world blew itself up here," says Dick Diver in Scott Fitzgerald's Tender is the Night. He is talking about the Somme, but the words might apply equally well to the World Trade Centre. Our lovely safe world has blown up too, and it remains to be seen how effectively we can repair it.

Some habits of daily life have already changed. In America the balance between civil liberties and the need to enhance security has been tilted sharply in the direction of the latter. But that trend was already apparent before 11 September – and not only in the US. That outrage simply accelerated it. The novelty of armed troops patrolling American air terminals still jars the traveller – until you remember that they have long done so routinely almost everywhere in Europe and the Middle East.

But suppose the worst; that a nuclear bomb takes out downtown Chicago, Los Angeles or New York. America would still remain the overwhelmingly dominant global power, unmatched in its military and economic might, as well as in its "soft power" of technological innovation and cultural influence, the same combination of advantages that underpinned imperial Rome almost two millennia ago. The suicide attacks were an unwitting tribute to that fact.

The US is not the equivalent of late 11th-century Byzantium or the British empire after the First World War, crumbling cornerstones of a vanishing world order. Bloody indignities may be inflicted upon it, but America – like Rome – will weather them. "Varus, Varus, give me back my legions," cried a heartbroken Emperor Augustus after the shattering Roman defeat in Germany in 9AD. But the empire survived the humiliation and lasted another 400 years.

Like it or loathe it, the US is a modern Rome. Accordingly, the place of 11 September in history will be determined not by what radical Islam does, but by what America does next. The risk is thus exactly the opposite of what it seemed three months ago: not an America brought to its knees, but an America so confident of the might of its arms and rightness of its cause that it feels able to move against any country of which it disapproves, starting with Iraq. This would truly be an "ugly America".

Nor, just as with so much supposedly set in motion by 11 September, would the trend be new. Only last summer the talk was of a new US unilateralism – how Washington had dismissed the Kyoto global warming treaty, trashed the proposed International Criminal Court, spurned plans to strengthen a United Nations germ warfare agreement and threatened to withdraw from the Anti Ballistic Missile Treaty (a step it has subsequently taken) to pursue the dream of a missile defence shield. The temptations to go it alone are now even stronger. If the US succumbs to them, the attacks will have changed nothing.

A second perfectly possible scenario, of course, is that nothing does change. Osama bin Laden will be, if not dead, a spent force. The recession will end. Corporations, diplomats and the rest of us will return thankfully to "business as usual". The "sacrifice" demanded by President Bush of his countrymen will shrink to an ability to put up with longer airport security queues. The mess in the Middle East will continue, and somewhere people will be plotting to infect or blow up not just two skyscrapers, but an entire city.

But there is a third option. America and the rest of us might see the horror of 11 September for what it also was: a twisted scream of pain from the have-nots and the dispossessed of an ever more divided world. If we act accordingly, then a day of horror might not have been in vain. To tackle the problems that indirectly led to 11 September would be to everyone's long-term advantage. The cost would be considerable, diplomatically and economically – but no more so than the enlightened self-interest of the 1947 Marshall Plan, which helped to rescue a Europe threatened with Communist takeover.

This time the focal point of the crisis is the Middle East, and the threat is radical Islam. Now, as then, an injection of Western aid is needed, with no strings attached. There must be an unselfish new trade round opening rich-country markets to the Third World, again with no strings attached. International financial institutions such as the International Monetary Fund, in effect controlled by the US, must cease forcing upon countries rigid free-market therapies that merely deepen their economic misery and enlarge the army of the hopeless.

The burden does not fall on the United States alone. Its Western allies have as much interest in drawing the teeth of radical Islam and in reducing dependence on Middle East oil. But America is at the epicentre. It alone has the power to shift the parameters of the Middle East conflict, distorted by its bias towards Israel. It is American troops who are stationed close to Islam's holy shrines. As long as this perceived humiliation by the infidel remains, Osama bin Laden will have a grievance to exploit. Only America, not Britain, France or Russia, can bring pressure on the corrupt and authoritarian regimes that supply us with oil to supply their own young peoples with political and economic futures.

The events of 11 September have reminded America of all these truths. If America does not respond to them, that terrible autumn day will only be the harbinger of worse to come.