Washington ? The curtain soon will go up on Act Three of the American experience in Iraq, even as its original authors scribble away behind the scenes, trying to determine whether the war eventually ends as Shakespearean tragedy, Hollywood action film or a cautionary moral fable of hubris and its consequences.

It has had elements of all three, from the lightning march to Baghdad to an Act Two full of unsettling gore, sinister intrigue and smashed expectations. As tragic scenes drag on interminably on the small-screen stage of nightly television, polls show the national audience glancing nervously for an exit it does not yet see.

The Senate also criticized the Bush administration’s current muddled text last week by calling on the White House to make 2006 a year of “significant transition” toward “the successful completion of the mission” in Iraq.

The 79-19 vote obviously signals Republican nervousness over Iraq policy a year in advance of congressional elections. But that is only one sign of a quickening sense here and abroad that the next few months open a decisive and new period in President Bush’s beleaguered attempt to use Iraq to change the Middle East and the world.

U.S. military commanders are composing their own scenarios that point to a drawdown of 30,000 to 40,000 American troops – from a current force of about 140,000 – that will begin before the midterm elections. Bush has hinted at numbers of that magnitude, and roughly corresponding cuts in foreign coalition troops, in private White House meetings, authoritative sources tell me.

The signs of impending change also trigger nervousness among allies. European diplomats have begun probing U.S. officials to determine whether NATO and other allies will face new pressure to shoulder financial and other burdens that the Americans want to lighten for themselves in Iraq’s year of transition.

The Europeans are aware that the administration has already put oil-rich Arab states on notice that their relations with Washington will be affected by whether they provide more aid to the permanent Iraqi government that is to emerge from Dec. 15 elections.

Last weekend’s sudden, very brief visit by U.N. Secretary-General Kofi Annan to Baghdad may also reflect concern in the world organization over being asked to play a larger role in transitional Iraq. Under U.S. and British prodding, Arab League officials also have reluctantly visited the Iraqi capital to meet many of the civilians who will form a new government after the elections.

But U.S. reconstruction and pacification efforts have not moved quickly or smoothly enough to rally the support Washington now seeks from others. The United States is unlikely to get significant help on Iraq from other nations, or from multilateral organizations, that feel they were ignored or defied by the Bush administration in Act One.

Americans will have to extricate themselves from a script that is largely of their own making. Their only significant help will come from Iraqis, and it will come unevenly even in the best of times.

The administration and an increasingly restive American public need to accept and focus on that reality, as control shifts from American hands to the Iraqis. The transition that the U.S. Senate is saying must come is about to begin -for better or for worse. It will not be reversed.

That means Americans should stay out of the December elections rather than channel covert help through Jordan’s King Abdullah or other Arab proxies, as happened in January. It means ending the covert control that the Central Intelligence Agency exercises over the Iraqi Intelligence Service, which does not report to or get funds from the Iraqi government. And it means finding a way to turn Iraq into a subject of dialogue rather than conflict with neighboring Iran.

A sign that the latter condition may be possible despite the increasing tensions over Iran’s nuclear ambitions lies in the recent political and physical travels of Ahmed Chalabi, Iraq’s best-known and therefore most reviled politician in the West.

Chalabi was given a high-profile welcome in Tehran by Iran’s Islamic revolutionaries – even though he recently split with the Islamic parties that Iran normally supports in Iraq and will be competing against them for votes in December – on his way to similarly laudatory high-level meetings in Washington.

For differing reasons, President Bush and the ayatollahs would, if they could, choose to have their own Iraqis in charge rather than hedge their bets with the hard-to-control Chalabi. But neither Tehran nor Washington is prepared to insult the future – which both are slowly realizing they cannot dictate alone.