What an amazing bloody catastrophe. The Bush administration's policy towards the Middle East over the five years since 9/11 is culminating in a multiple train crash. Never in the field of human conflict was so little achieved by so great a country at such vast expense. In every vital area of the wider Middle East, American policy over the last five years has taken a bad situation and made it worse.

If the consequences were not so serious, one would have to laugh at a failure of such heroic proportions - rather in the spirit of Zorba the Greek who, contemplating the splintered ruins of his great project, memorably exclaimed: "Did you ever see a more splendiferous crash?" But the reckless incompetence of Zorba the Bush has resulted in the death, maiming, uprooting or impoverishment of hundreds of thousands of men, women and children - mainly Muslim Arabs but also Christian Lebanese, Israelis and American and British soldiers. By contributing to a broader alienation of Muslims it has also helped to make a world in which, as we walk the streets of London, Madrid, Jerusalem, New York or Sydney, we are all, each and every one of us, less safe. Laugh if you dare.

In the beginning, there were the 9/11 attacks. It's important to stress that no one can fairly blame George Bush for them. The invasion of Afghanistan was a justified response to those attacks, which were initiated by al-Qaida from its bases in a rogue state under the tyranny of the Taliban. But if Afghanistan had to be done, it had to be done properly. It wasn't. Creating a half-way civilised order in one of the most rugged, inhospitable and tribally recalcitrant places on the planet was always going to be a huge challenge. If the available resources of the world's democracies, including those of a new, enlarged Nato, had been dedicated to that task over the last five years, we might at least have one partial success to report today.

Instead Bush, Cheney and Rumsfeld drove us on to Iraq, aided and abetted by Tony Blair, leaving the job in Afghanistan less than half-done. Today Osama bin Laden and his henchmen are probably still holed up in the mountains of Waziristan, just across the Afghan frontier in northern Pakistan, while the Taliban is back in force and the whole country is a bloody mess. Instead of one partial success, following a legitimate intervention, we have two burgeoning disasters, in Afghanistan and in Iraq.

The United States and Britain invaded Iraq under false pretences, without proper legal authority or international legitimacy. If Saddam Hussein, a dangerous tyrant and certified international aggressor, had in fact possessed secret stockpiles of weapons of mass destruction, the intervention might have been justified; as he didn't, it wasn't. Then, through the breathtaking incompetence of the civilian armchair warriors in the Pentagon and the White House, we transformed a totalitarian state into a state of anarchy. Claiming to move Iraq forward towards Lockean liberty, we hurled it back to a Hobbesian state of nature. Iraqis - those who have not been killed - increasingly say things are worse than they were before. Who are we to tell them they are wrong?

Now we are preparing to get out. After working through Basra in Operation Sinbad, a reduced number of British troops will draw back to their base at Basra airfield. We will sit in a desert and call it peace. If the White House follows the Baker-Hamilton commission's advice, US troops will do something similar, leaving embedded advisers with Iraqi forces. Three decades ago, American retreat was cloaked by "Vietnamisation"; now it will be cloaked by Iraqisation. Meanwhile, Iraqis can go on killing each other all around, until perhaps, in the end, they cut some rough-and-ready political deals between themselves - or not, as the case may be.

The theocratic dictatorship of Iran is the great winner. Five years ago, the Islamic republic had a reformist president, a substantial democratic opposition, and straitened finances because of low oil prices. The mullahs were running scared. Now the prospects of democratisation are dwindling, the regime is riding high on oil at more than $60 a barrel, and it has huge influence through its Shia brethren in Iraq and Lebanon. The likelihood of it developing nuclear weapons is correspondingly greater. We toppled the Iraqi dictator, who did not have weapons of mass destruction, and thereby increased the chances of Iran's dictators acquiring weapons of mass destruction. And this week Iran's President Ahmadinejad once again called for the destruction of the state of Israel. Those American neocons who set out to make the Middle East safe for Israel have ended up making it more dangerous for Israel.

We did not need an Iraq Study Group to tell us that resolving the Arab-Israeli conflict through a two-state solution for Israel and Palestine is crucial. In its last months the Clinton administration came close to clinching the deal. Under Bush, things have gone backwards. Even the Bush-backed Ariel Sharon scenario of separation through faits accomplis has receded, with the summer war in Lebanon, Hamas ascendancy in Palestine (itself partly a by-product of the Bush-led rush to elections), and a growing disillusionment of the Israeli public.

Having scored an apparent success with the "cedar revolution" in Lebanon and the withdrawal of Syrian troops, the Bush administration, by its tacit support of sustained yet ineffective Israeli military action this summer, undermined the very Lebanese government it was claiming to support. Now Hizbullah is challenging the country's western-backed velvet revolutionaries at their own game: after the cedar revolution, welcome to the cedar counter-revolution. In Egypt, supposedly a showcase for the United States' support for peaceful democratisation in the Bush second term, electoral success for Islamists (as in Palestine and Lebanon) seems to have frightened Washington away from its fresh-minted policy before the ink was even dry. On the credit side, all we have to show is Libya's renunciation of weapons of mass destruction, and a few tentative reforms in some smaller Arab states.

So here's the scoresheet for Afghanistan, Iraq, Iran, Israel, Palestine, Lebanon and Egypt: worse, worse, worse, worse, worse, worse and worse. With James Baker, the United States may revert from the sins of the son to the sins of the father. After all, it was Baker and George Bush Sr who left those they had encouraged to rise up against Saddam to be killed in Iraq at the end of the first Gulf war - not to mention enthusiastically continuing Washington's long-running Faustian pact with petro-autocracies such as Saudi Arabia. I'm told that Condoleezza Rice, no less, has wryly observed that the word democracy hardly features in the Baker-Hamilton report.

Many a time, in these pages and elsewhere, I have warned against reflex Bush-bashing and kneejerk anti-Americanism. The United States is by no means the only culprit. Changing the Middle East for the better is one of the most difficult challenges in world politics. The people of the region bear much responsibility for their own plight. So do we Europeans, for past sins of commission and current sins of omission. But Bush must take the lion's share of the blame. There are few examples in recent history of such a comprehensive failure. Congratulations, Mr President; you have made one hell of a disaster.

timothygartonash.com