Launched by US-led forces three weeks ago without United Nations approval, the war triggered sharp divisions both within the UN Security Council and NATO, two key institutions to which the United States belong.

It also created a deep split within the European Union, a key political and trade partner of Washington.

Several of Washington's Arab allies, such as Egypt and Saudi Arabia, are deeply concerned about US plans to turn Iraq into a democratic model that could be used as a magnet to reshape the entire Middle East.

President George W. Bush's administration has also used the conflict to test the "coalition of the willing" concept to manage international crises.

Free from the constraints of traditional international institutions, such US-led ad hoc coalitions could be used again to pursue Washington's policy goals.

The war also tested the concepts of "preemptive war" and "regime change" in response to perceived threats to US national security, in a major break with traditional strategic and international norms.

In doing so, Washington sparked deep unease among long-standing allies such as France and Germany but also with Russia despite a spectacular rapprochement between Washington and Moscow in recent years.

This crisis could lead Washington to strengthen its ties with former communist east European states which back the US views on Iraq, unlike "Old Europe", the derisive term used by Defense Secretary Donald Rumsfeld to describe France and Germany.

William Kristol, an influential neo-conservative columnist, argues that the time has come to take a hard look at Washington's alliances.

"At the end of the day, our priority has to be dealing with these dangers, not placating allies who are more concerned with the exercise of American power than the threats we face," he told the Senate Foreign Relations Committee on Tuesday.

But Peter Galbraith, an international affairs expert at the National War College here, also stressed the need for Washington to ease international tensions and cooperate with traditional institutions such as the UN.

"(In Iraq) What is the final exit strategy? It is holding an election. If the UN does it, nobody will question its legitimacy," he noted. "The UN actually does a very good job with holding elections in post conflict situation."

Meanwhile Vice President Dick Cheney sounded a conciliatory note. Referring to the crisis with Germany and France, he said: "That's history, that's behind us now."

"With respect to those who didn't support the effort, perhaps time will help in terms of improving their outlook. I think once they see the results of our efforts that they'll be interested in trying to help, at least on the humanitarian side, and that's appropriate," he said.

"Hopefully should similar problems arise in the future, maybe our French and German friends will reconsider their position," he added.

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