As an outsider I can only hope that these efforts prove salutary and productive. As an Iranian, however, I am concerned with the possible consequences of what is now being speculated.

In the past, I have repeatedly opposed any form of military action against my country as counterproductive. Today, I would like to be equally clear about expectations that Iran - and Syria for that matter - could become part of the solution in Iraq.

For some time, guilt-edged liberal opinion in America has been advocating engagement with the clerical regime in Iran. Diplomatic overtures and dialogue, inherently noble, should be the first resort in any conflict. But if policymakers wish to avoid disappointment, there needs to be a prior analysis of objectives. In this context: what is at stake, and what are the real chances of success in hoping that Iran will sanitise the climate in Iraq in a manner that is in line with US expectations?

If the US seeks Iran's cooperation in Iraq - in taming and disarming the feuding Shi'a (and Tehran-connected) militias run by Ayatollah Abdul-Aziz al-Hakim and Muqtada al-Sadr, or in encouraging prime minister Nouri al-Maliki to move towards power-sharing with the Sunni - a key question follows: what would be the Iranian rulers' price?

What price would the Islamic regime claim in exchange for undercutting its unearned foothold in Iraq, at a time when it regards the US and its global allies with acute hostility? If that price is a license to proceed with its opaque pursuit of dual-usage enrichment of uranium, could the Bush administration seriously contemplate it?

If, by contrast, Tehran seeks from any engagement a grand strategic bargain - encompassing (as well as the nuclear issue) Hizbollah, Hamas, jihadis, non-belligerence towards Israel, and a Palestinian settlement - then a different set of questions comes to mind.

In May 2003, the clerical regime signalled its willingness to come to terms with reality. The move's timing - barely a month after the lightning defeat of Saddam Hussein - speaks volumes about the motivations of Tehran's Islamist leadership. Now, circumstances have changed dramatically. The "awe" inspired by the United States blitzkrieg is replaced by contempt, meted out on a daily basis by Islamist president, Mahmoud Ahmadinejad.

Ahmadinejad, unlike his predecessor Mohammad Khatami, is a revolutionary revivalist. His powers are limited but his rhetoric has enthralled the ultra-conservative clerics and tied the hands of the more pragmatic elements. The notion of the Great Satan, in the psyche of genuine Khomeini disciples, is ideological. For them, America is the embodiment of corrupting influences that are detrimental to Islam's flourishing.

America is also seen as the architect and protector of the Jewish state and its perceived mortification of (Muslim) Palestinians. The feud against Israel, extending to holocaust-denial, has set the regime in a hostile mould. Only compelling reasons of self-preservation will alter this. Moreover, with the Islamic Republic in its current mindset, secure in cost-free intransigence, any dialogue - particularly one wishfully aimed at cushioning America's difficulties in Iraq - will achieve nothing other than to bestow unwarranted recognition and legitimacy to a rogue regime.

There is another side to such engagement. For twenty-seven years this theocracy has cast a pall over Iran. Its young population has been robbed of the chance to live the epoch in which they are born. A full generation has been traumatised, prisoners of conscience executed and dissidents murdered in their homes or forced to flee.

George W Bush has repeatedly pledged America's support of Iranians in their struggle for freedom and democracy. To engage with the current Islamic Republic in these circumstances would render America's moral pact hollow and meaningless. It would be a further tragedy if, after failing to introduce democracy by force in Iraq, Washington now underwrites tyranny by diplomacy in Iran.