America will brush aside our concerns and attack Saddam in the spring

The problem for us all is the hatred we cannot see, which feeds on the growing sense of humiliation in the Arab world

All week the argument has raged, so I offer not opinion but instead some predictions. Always a risk, I know, but here's the first prediction. By this time next year a war will have been fought in Iraq, and, barring an extraordinary upset, we will be speaking of Saddam Hussein in the past tense. Hardly a radical forecast you might say, but in a week that saw opposition to war strengthen here in Britain and across Europe, it might be tempting to believe that President Bush has been given food for thought, that he might be re-thinking his strategy of toppling Saddam.

Such hope, however, is not founded on prevailing realities. It reflects a disconnection from the new global politics. We have entered the era of the American imperium in which the logic of the Monroe doctrine (by which the US justified intervention in Latin America at the turn of the last century) has been extended to embrace the globe. One of the most important messages of the aftermath of 11 September is that the world is now America's backyard. That is why we see US special forces operating in theatres as far apart as the Phillipines and the Caucusus. For the architects of the new foreign policy, a regime change in Iraq is not merely desirable but essential.

One of Mr Bush's most prominent advisers made it clear in a newspaper article yesterday. The US would go it alone and attack Iraq even if Britain or other allies demurred. America will do it because it can and because President Bush and the Washington "hawks" upon whom he increasingly depends for strategic guidance want to do it.

So no surprise that the author of the article, Richard Perle, dismisses much of the opposition to the war as "the feckless moralising of 'peace' lobbies or the unsolicited advice of retired generals". He summons up the ghost of Munich and implicitly accuses the war's opponents of appeasement and likens Saddam Hussein to Hitler; one must ask if he remembers that similar language was employed in the run-up to the disastrous invasion at Suez more than four decades ago. Then Nasser was compared to Hitler though few in Britain – and nobody in Washington – really believed it.

But comparisons with Suez only go so far. The attack on Nasser was the last squeak of a dying imperial order. Britain and France, aided by Israel, set out to impose their will much in the same way that General Gordon had been dispatched to deal with the Mahdi or the Foreign Legion to quell the restive tribes of North Africa. Today the enforcer is not some enfeebled imperial power but the world's only superpower; where President Eisenhower was able to halt the Suez operation with a few phone calls, the people who oppose the war in Iraq have no such leverage, though we might see cabinet resignations, perhaps even the unprecedented spectacle of large numbers of the British public protesting about a war far from their shores.

So if a war is going to happen, how will it be fought and when? Again a prediction: the war will be launched early in the spring using massive airpower and special forces. It will not be an attack involving a vast army, but neither will be it confined to raiding parties of American Delta Force and the SAS. Talk of force deployments in the region of 70,000 to 150,000 is probably closer to the mark than the figure of a quarter of a million quoted recently. One ex-soldier who fought in the last Gulf War told me he believes the Americans are convinced they can repeat the strategy used in Afghanistan and will rely heavily on Kurdish, Shia and Iraqi exile groups to do the dying when it comes to fighting in the Iraqi cities.

And it is here we enter the great unknown. Will America attack? Yes. Will it get rid of Saddam? Yes. But how many people will die in the process and what will the effects of all of this be in the Middle East?

We know from experience that the air campaign that precedes any ground offensive will claim civilian lives. There is also the fact that the Iraqi army has nowhere to run. Memories of the Gulf War slaughter of Mutla Ridge will be fresh in the minds of the armoured commanders, and the infantry will be cut off in virtually all directions. A retreat into Iran or the Kurdish populated north is out of the question, so too any rush south towards Kuwait. That leaves Jordan and Saudi Arabia, neither of which will want to see an influx of fleeing Iraqi divisions. So the option is to surrender or to die.

While many of the conscripts will doubtless choose the former option, there is no such certainty about the Republican Guard, not to mention the danger that Saddam will launch at least some weapons of mass destruction in the direction of Israel or at advancing allied forces. The Americans clearly hope that he will be dead – a victim of an assassin's bullet or a precision bomb -– before that moment arises. But it is an optimistic calculation that leaves room for catastrophic upset.

At the moment there is no clear contender to replace Saddam, though American officials will point out that a similar uncertainty prevailed in Afghanistan prior to the toppling of the Taliban. But Afghanistan does not present the wisest map for the latter day king-makers in the White House. Beset by internal rivalries, the government of Hamid Karzai is in a precarious position and the gunmen of al-Qa'ida and the Taliban are far from vanquished – witness the attack that took place in Kabul's suburbs this week. There are some respects in which creating a new government in Afghanistan may have been easier, simply because of the proliferation of factions. None had the individual power to confront America and there was never going to be any chance they would come together as allies.

Mr Bush has been told he runs the risk of creating massive instability in a region already seething with resentment, and in some countries outright hatred, of the US. The risk to the regimes in Saudi Arabia and Jordan is clear. The toppling of an Arab government by a foreign power on their doorsteps will leave the Saudis and others looking impotent in the eyes of their increasingly radicalised populations. It may be that such predictions are overly gloomy, that we will see a short war with few civilian casualties and the replacement of Saddam with a democratic head of state. The Arab world will protest and burn flags but nothing much else will happen, though many senior foreign policy experts on this side of the Atlantic seem to doubt that.

The greatest danger lies in the rapid growth of anti-Western feeling in the Middle East; forces like al-Qa'ida which thrive on resentment of America will strengthen in the event of war. Some American policymakers acknowledge this but believe the risk is worth taking in order to destroy Saddam. The problem for all of us is the hatred we cannot see, which feeds on the rising sense of humiliation in the Arab world and is already recruiting its next generation of killers. The embodiment of that hatred, al-Qa'ida, is waiting for its chance. The challenge is to construct a political way forward that neutralises the hatred without compromising our security. Politics is the key, but it demands time and attention and no end of patience.

The writer is a BBC Special Correspondent