There was always a risk for Bin Laden that worldwide sympathy for the US might thwart his long-term aim of holy war against the Great Satan. He needn't have worried. With the Bush junta at the helm, a camel could have foreseen the outcome. And the beauty is that it doesn't matter what happens in the war.

Imagine how it looks from Bin Laden's warped point of view...

If the American victory is swift, Bush will have done our work for us, removing the hated Saddam and opening the way for a decent Islamist government. Even better, in 2004 Bush may actually win an election. Who can guess what that swaggering, strutting little pouter-pigeon will then get up to, and what resentments he will arouse, when he finally has something to swagger about? We shall have so many martyrs volunteering, we shall run out of targets. And a slow and bloody American victory would be better still.

The claim that this war is about weapons of mass destruction is either dishonest or betrays a lack of foresight verging on negligence. If war is so vitally necessary now, was it not at least worth mentioning in the election campaigns of 2000 and 2001? Why didn't Bush and Blair mention the war to their respective electorates? The only major leader who has an electoral mandate for his war policy is Gerhard Schroder - and he is against it. Why did Bush, with Blair trotting faithfully to heel, suddenly start threatening to invade Iraq when he did, and not before? The answer is embarrassingly simple, and they don't even seem ashamed of it. Illogical, even childish, though it is, everything changed on September 11 2001.

Whatever anyone may say about weapons of mass destruction, or about Saddam's savage brutality to his own people, the reason Bush can now get away with his war is that a sufficient number of Americans, including, apparently, Bush himself, see it as revenge for 9/11. This is worse than bizarre. It is pure racism and/or religious prejudice. Nobody has made even a faintly plausible case that Iraq had anything to do with the atrocity. It was Arabs that hit the World Trade Centre, right? So let's go and kick Arab ass. Those 9/11 terrorists were Muslims, right? And Eye-raqis are Muslims, right? That does it. We're gonna go in there and show them some hardware. Shock and awe? You bet.

Bush seems sincerely to see the world as a battleground between Good and Evil, St Michael's angels against the forces of Lucifer. We're gonna smoke out the Amalekites, send a posse after the Midianites, smite them all and let God deal with their souls. Minds doped up on this kind of cod theology have a hard time distinguishing between Saddam Hussein and Osama bin Laden. Some of Bush's faithful supporters even welcome war as the necessary prelude to the final showdown between Good and Evil: Armageddon followed by the Rapture. We must presume, or at least hope, that Bush himself is not quite of that bonkers persuasion. But he really does seem to believe he is wrestling, on God's behalf, against some sort of spirit of Evil. Tony Blair is, of course, far more intelligent and able than Bush. But his unshakable conviction that he is right and almost everybody else wrong does have a certain theological feel. He was indignant at Paxman's wickedly funny suggestion that he and Dubya pray together, but does he also believe in Evil?

Like sin and like terror (Bush's favourite target before the Iraq distraction) Evil is not an entity, not a spirit, not a force to be opposed and subdued. Evil is a miscellaneous collection of nasty things that nasty people do. There are nasty people in every country, stupid people, insane people, people who should never be allowed to get anywhere near power. Just killing nasty people doesn't help: they will be replaced. We must try to tailor our institutions, our constitutions, our electoral systems, so as to minimise the chance that such people will rise to the top. In the case of Saddam Hussein, we in the west must bear some guilt. The US, Britain and France have all, from time to time, done our bit to shore up Saddam, and even arm him. And we democracies might look to our own vaunted institutions. Are they well designed to ensure that we don't make disastrous mistakes when we choose our own leaders? Isn't it, indeed, just such a mistake that has led us to this terrible pass?

The population of the US is nearly 300 million, including many of the best educated, most talented, most resourceful, humane people on earth. By almost any measure of civilised attainment, from Nobel prize-counts on down, the US leads the world by miles. You would think that a country with such resources, and such a field of talent, would be able to elect a leader of the highest quality. Yet, what has happened? At the end of all the primaries and party caucuses, the speeches and the televised debates, after a year or more of non-stop electioneering bustle, who, out of that entire population of 300 million, emerges at the top of the heap? George Bush.

My American friends, you know I love your country, how have we come to this? Yes, yes, Bush isn't quite as stupid as he sounds, and heaven knows he can't be as stupid as he looks. I know most of you didn't vote for him anyway, but that is my point. Forgive my presumption, but could it just be that there is something a teeny bit wrong with that famous constitution of yours? Of course this particular election was unusual in being a dead heat. Elections don't usually need a tie-breaker, something equivalent to the toss of a coin. Al Gore's majority in the country, reinforcing his majority in the electoral college but for dead-heated Florida, would have led a just and unbiased supreme court to award him the tie-breaker. So yes, Bush came to power by a kind of coup d'etat. But it was a constitutional coup d'etat. The system has been asking for trouble for years.

Is it really a good idea that a single person's vote, buried deep within the margin of error for a whole state, can by itself swing a full 25 votes in the electoral college, one way or the other? And is it really sensible that money should translate itself so directly and proportionately into electoral success, so that a winning candidate must either be very rich or prepared to sell favours to those who are?

When a company seeks a new chief executive officer, or a university a new vice-chancellor, enormous trouble is taken to find the best person. Professional headhunting firms are engaged, written references are taken up, exhaustive rounds of interviews are conducted, psychological aptitude tests are administered, confidential positive vetting undertaken. Mistakes are still made, but it is not for want of strenuous efforts to avoid them. Maybe such methods would be undemocratic for choosing the most powerful person on earth, but just think about it. Would you do business with a company that devoted an entire year to little else than the process of choosing its new CEO, from the strongest field in the world, and ended up with Bush?

Saddam Hussein has been a catastrophe for Iraq, but he never posed a threat outside his immediate neighbourhood. George Bush is a catastrophe for the world. And a dream for Bin Laden.

・ Richard Dawkins FRS is the Charles Simonyi Professor at Oxford University. His latest book is A Devil's Chaplain (Weidenfeld & Nicholson).