Washington ? A black hole in the U.S. commitment to transform the Greater Middle East hovers over Iran. An attentive newspaper reader can describe the goals that President Bush and Condoleezza Rice, his national security adviser, have in mind with respect to Iraq, Palestine and the Arab political order. On Iran, the jury of two is still out.

That is not a bad place for them to be. Iran’s volatile internal politics — and the strategic changes created by U.S. troops camping on Iran’s borders and new international pressure on Tehran to give up its nuclear weapons program — make planning ahead and staying flexible prudent.

There is no doubt about Bush’s assessment of the nature of the ayatollahs’ regime. His “axis of evil” designation in January 2002 made that clear. But he has noticeably failed to take up the suggestions of some U.S. hawks that the ayatollahs are about to fall and need only a little push, or that Iran should automatically be “next” on a pre-emption list.

Bush went out of his way in his last news conference to endorse the recent diplomatic initiative by France, Germany and Britain that got Iranian agreement to more intrusive inspections and to halt reprocessing fissionable material usable for bombs. That diplomatic high road is not the path a president looking for a chance to bash the ayatollahs militarily would take.

As it has with North Korea, the administration has “multilateralized” the drive to contain Iran’s nuclear ambitions. And behind the scenes, the United States has exerted heavy pressure on Pakistan to halt its clandestine nuclear cooperation with Iran and, with less success, tried to halt Russia’s scheduled nuclear fuel shipments to Iran.

There is a refreshing lack of certainty at senior levels of this often absolutist administration about Iran. Rice is said to have recently scrawled a plaintive query on a memo to an associate asking why American policy-makers have had such a consistent record of guessing wrong on Iran.

Good question. Iran has been in constant ferment for half a century. Movement toward a more open and/or secular society is constantly checked by the ayatollahs, only to resume again. One of the world’s most ancient nations is infuriatingly postmodern and enigmatic in its politics.

But now that Rice is spearheading the president’s most ambitious foreign policy initiative — the political transformation of the Greater Middle East and, indirectly, the Muslim world — Iran cannot for long be left as a blank to be filled in later. Events, especially in Iraq, are dragging the Persians and the Americans toward either new accommodation or bitter and dangerous conflict.

Geography and religion give Iran inordinate interest in and influence over Iraq, which Tehran has chosen to exercise quietly and slowly since the coalition invasion. Bush’s earlier threatening words toward Iran and his bold action in Iraq have shaped a new strategic landscape that the ayatollahs also approach warily.

Instead of urging their co-religionists in Iraq’s Shiite majority to oppose the occupation and support the insurgency, the Iranians have kept a low profile. “They are building up their presence and their influence in low-key ways. They play for the future. They want us to fail in Iraq. But they want us to fail slowly,” says one senior U.S. official.

Iraq’s appointed leaders have been careful to keep Iran informed and indirectly engaged in the nascent political process that is under way in their occupied country. Their actions suggest that a liberated and stable Iraq could serve as a bridge between Washington and Tehran.

Ahmed Chalabi, head of the Iraqi National Congress, recently visited Tehran and had a widely publicized meeting with President Mohammad Khatami. Kurdish leader Jalal Talabani is a frequent visitor to Iran. The current president of the Iraq’s Governing Council, Abdul Aziz Hakim, is a Shiite cleric who is close to the senior hard-liners in the Iranian regime.

So it did not go unnoticed in Washington last week when Hakim and Talabani went to Paris and were effusively welcomed by Foreign Minister Dominique de Villepin. Iran is the only available counterweight in the Greater Middle East if France and Russia decide to challenge the now-dominant American position in Iraq and Saudi Arabia. Iran could be a bridge of a different kind for them if the current Bush effort to mend fences in Paris and Moscow falls short.

American success — or American failure — in Iraq leads inevitably to a greatly changed U.S. relationship with Iran. It is time to be asking, as Condi Rice is, how Washington can get it right this time.

Jim Hoagland is a columnist for Washington Post Writers Group.