It has been another awful week for Tony Blair, perhaps even worse than the mid-summer meltdown triggered by his fatally misjudged support for the Israeli invasion of Lebanon. First there was the craven surrender to Saudi Arabia’s demand for the suspension of Britain’s anti-corruption laws if they impinge on the personal finances of Saudi princes. Next came the derisive rejection of Mr Blair’s latest effort to “kick-start the Middle East peace process” by every leader in the region. This was followed by the devastating report from Britain’s leading foreign policy institute, explaining how the Prime Minister had subordinated national interests to his unrequited love affair with President Bush. Then to cap it all, Britain’s supposed ally, the Iraqi Vice-President, commented that Mr Blair had been “brainwashed” and “blackmailed” by Mr Bush.

Nobody much cares any longer if Mr Blair rushes towards political perdition, but will his few remaining months in office sabotage the prospects of future Labour governments for years to come? The Chatham House report about the “disaster” of Mr Blair’s foreign policy is surprisingly sanguine about the willingness of future prime ministers to change course: “His successor(s) will not make the same mistake. For the foreseeable future, whoever is prime minister, there will no longer be unconditional support for US initiatives in foreign policy.”

If only things were so simple. With every day that passes, Gordon Brown, through his silence on foreign policy, is closing off the options which should be available to the next prime minister. Having failed to hint at any objections to the conduct of the Iraq war or to Washington’s Middle East policies, Mr Brown is starting to get personally locked into the Blair-Bush axis. If he remains silent on foreign affairs much longer, Mr Brown will find it difficult to undertake the radical shift in British diplomacy that many of his supporters have been expecting and which Chatham House now describes as inevitable and necessary for Britain’s national interest.

The difficulty of executing a foreign policy U-turn if Mr Brown takes over, presumably sometime in June, will be greatly exacerbated if events in Washington and the Middle East continue to accelerate at their present pace. The problem is not just that the security situation in Iraq is deteriorating, but that the Bush-Blair duo are ruling out sensible options and creating new enemies almost every time they open their mouths.

Take yesterday’s speech in Dubai, in which Mr Blair denounced Iran and called for an “alliance of moderation” to challenge this founder member of what Mr Bush called the “Axis of Evil”.

“They seek to pin us back in Lebanon, in Iraq and in Palestine. Our response should be to expose what they are doing, build the alliances to prevent it and pin them back across the whole of the region,” he declared. This overtly bellicose speech, which came closer to a declaration of war than anything heard from the West since the “Axis of Evil” address, undermined months of patient diplomacy by British, European and even unofficial US representatives, such as James Baker, who had been trying to isolate the extremists in the Iranian Government and to explain to the Bush Administration that stability in Iraq and the Middle East would be impossible without some kind of rapprochement between Washington and Tehran.

Even more embarrassingly, Mr Blair delivered his diatribe just days after Iran held a reasonably fair election that resulted in a victory for the country’s more pragmatic politicians and a considerable setback for its anti-Western extremists. Mr Blair constantly cites the supposed democracy in Iraq as the main reason for persisting with the Occupation and hoping for stability. But now he describes the Government produced by Iranian democracy, which for all its flaws seems no worse than the Iraqi version, as the greatest “strategic threat” in the region.

Considering that only two weeks ago, Mr Blair seemed to support the Baker commission’s call for a dialogue with this very same Iranian Government, “brainwashing” may well be the correct word to describe what happened to him in Washington last week.

Most bizarrely of all, Mr Blair’s identification of Iran as the source of the “ideological battle” that would dominate the 21st century came less than a week after his very personal interaction with the country that really is the financial and spiritual homeland of al-Qaeda, the 9/11 terrorists and the majority of foreign insurgents fighting in Iraq.

This country is, of course, Saudi Arabia. That Saudi Arabia remains deeply involved in the terrorist nexus was implicitly acknowledged by Mr Blair himself when he declared last week that Britain would face a greater risk of terrorist attack if the Saudi Government withdrew its security co-operation. That the Saudi Government has made its security co-operation conditional on Mr Blair blocking any further investigations into the sweeteners paid to Saudi princes by British companies shows the shallowness of the country’s supposed commitment to the War on Terror.

The Saudis’ ambivalence in the war against jihadi radicalism is hardly surprising, since extremist interpretations of Islam remain far more dominant in Saudi society than they have ever been in Iran or any Middle Eastern country other than Afghanistan under the Taliban.

Moreover, the radicalisation of previously quiescent Muslim populations from Indonesia and Turkey to Britain, Spain and France, continues to be directly funded by the Saudi money pouring into Sunni mosques and madrassas inspired by the extremist Wahhabi sect. If, as Mr Blair suggests, the 21st century will be marked by an ideological struggle between Western civilisation and Islamic extremism, the main battles will have to be fought with Saudi Arabia, not Iran.

Why, then, have Mr Blair and Mr Bush identified Iran as the main enemy in the struggles that lie ahead? There seems to be only one plausible answer. Iran may be closer to democracy and less involved in anti-Western terrorism than other important Middle Eastern countries, but it is also much larger, more powerful and therefore potentially threatening to the interests of the two dominant, but inherently unstable, powers in the region — Saudi Arabia and Israel.

These two countries are now discouraging diplomatic rapprochement between Tehran and Washington and whispering in Mr Bush’s ear about the need to “contain” Iran. The natural corollary of this containment strategy could well be an Israeli military attack on Iran sometime next year.

If this is where the Middle East is heading, the next British prime minister will need to do more than distance himself from America. He may have to recognise Saudi Arabia and Israel as the root causes of much of the trouble in the Middle East. Are you listening, Mr Brown?

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