Should the United States install a "Pax Americana" at the risk of painting Iraq as a US protectorate, or should the UN flag fly over reconstruction efforts, with even France, Russia and Germany -- which vigorously opposed the war -- taking part?

Debate has rarely been so intense between neo-conservatives who favor an unabashed assertion of American preeminence, and internationalists who do not want to see the United States isolated from the world community.

"The war in Iraq has become as much a test of the international system as of Saddam Hussein, as much a question of a new world order as of a new, democratic Iraq," said Thomas Donnelly of the American Enterprise Institute (AEI), a Washington think tank.

The "new world order" that will emerge from the war will be a "unipolar world, marked by an even greater degree of American primacy and leadership than before," Donnelly said in an April 1 essay published by AEI, which is close to administration hawks including Vice President Dick Cheney and Defense Secretary Donald Rumsfeld.

"We appear to be moving at last from the post-Cold War era to the time of an enduring Pax Americana," he said, adding that new institutions may be needed "to reflect the new realities."

But other analysts disagree, arguing that the enormity of the task of rebuilding Iraq, coupled with the need to pursue a long-term campaign against international terrorism, will oblige Washington to rein in unilateralist impulses and seek broad cooperation within the United Nations.

"It is in US interests to use the UN," said Rachel Bronson of the New York-based Council on Foreign Relations.

"The UN provides legitimacy that makes the job (of rebuilding Iraq) a lot easier (and) can give the Iraqis themselves time to figure out how they can incorporate the exiles into the political system as well as those who have lived in Iraq."

Even Washington's best friends, beginning with British Prime Minister Tony Blair, are pressing for an international framework for the reconstruction of Iraq.

Following a two-day summit in Belfast, Bush and Blair on Tuesday denied a reported split over the role of the United Nations in supervising an interim Iraqi government.

The controversy has threatened to bring about a repeat of the bitter bickering between Washington and Europe that emerged during the run-up to the Iraq war and jeopardized the future of transatlantic ties.

"The rebuilding of Iraq will require the support and expertise of the international community," Bush said. "We're committed to working with international institutions, including the United Nations, which will have a vital role to play in this task."

In a joint statement, the two leaders restated their commitment to seeking new UN resolutions to "affirm Iraq's territorial integrity, ensure rapid delivery of humanitarian relief and endorse an appropriate post-conflict administration for Iraq."

Helmut Sonnenfeldt, an international affairs expert at the Brookings Institution, said debate on post-war Iraq at the United Nations in the coming weeks could be decisive in Bush's outlook on the issue.

"If it becomes just a resumption of the disputes and the arguments" that Washington rejected in its decision to lead a military campaign against Saddam, "the US probably will figure out other ways to work in Iraq."

If instead "all of the countries involved ... exercise moderation," the United Nations could have "a continuing role," Sonnenfeldt said.

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