While the tanks are moving towards Baghdad, the Washington think tanks are manoeuvring for influence in shaping the interpretation of the war.
Every morning in Washington journalists crowd into briefing rooms, not to hear the government's view of the war, but to listen to a bevy of outside experts.
Richard Perle leads the AEI briefing
Their competing views go a long way to shape the coverage of the war and our understanding of the peace.
And the rival think tanks, even though most favour the war, have a very different perspective to bring, often echoing the silent battles being fought within the Bush administration.
On Tuesdays, the leading neo-conservative think tank, the American Enterprise Institute, holds its "black coffee morning", a relatively sumptuous breakfast and talks by key Iraqi exiles as well as luminaries like Richard Perle, a leading hawk who is close to Defence Secretary Donald Rumsfeld.
It has been the neo-conservatives who talk of a war of liberation, and their optimism about the military progress of the war is tempered by their concern about losing the political battle.
Last week former CIA director James Woolsey spoke at the AEI briefing; soon after it was suggested in some newspapers that he would become head of information in the interim US government scheduled to take over in Iraq
They would have liked the US to go into battle with the Iraqi INC opposition group following on the ground behind them. They speak darkly of the "battle over the INC" being more intense than the battle for Baghdad.
Pickets and exiles
Anti-war pickets gather outside the building, while inside the standing-room only meeting is peppered with Republican congressional aides and Iraqi exiles.
Last week former CIA director James Woolsey spoke at the AEI briefing; soon after it was suggested in some newspapers that he would become head of information in the interim US government scheduled to take over in Iraq.
Just around the corner, in the heart of lobbyist Washington on K Street, is the Center for Strategic and International Studies.
Here, on Wednesdays, a very different view of the war is portrayed by its military expert, Anthony Cordesman, in its huge lecture hall where Colin Powell gave one of his main speeches just before a key United Nations vote.
He points to the difficulties of both the military and reconstruction task and, like many retired generals, urges more troops and more resources for the reconstruction effort.
A few blocks away, the sedate Brookings Institution - Washington's first think tank - holds forth on Thursday mornings.
It meets later - at 1000 not 0830 - and serves Starbucks coffee and croissants to the assorted journalists, many of whom are from the Middle East.
Many former members of the Clinton administration's foreign policy team take part, including their star speaker, Kenneth Pollack, who worked on Iraq issues both for the CIA and the National Security Council.
Mr Pollack's influential book, The Threatening Storm, argued for a war against Iraq because containment had failed and Saddam Hussein had to be disarmed soon.
But he is less optimistic about the easy progress of US troops, and much more concerned about rebuilding Iraq with the involvement of the UN. He also says there could be great difficulties ahead.
Mr Pollack is one of the foreign policy realists who are the targets of the neo-conservatives.
The realists see limits to US power and, in contrast to those at AEI, worry much more about alienating European allies.
Think tanks in a row
Even more objectionable to the neo-conservatives are the idealists, who want a multilateral world order based on the UN.
Their Washington base is the Carnegie Endowment for International Peace, next door to Brookings on Massachusetts Avenue.
Jessica Matthews, its president, had urged the US to give the UN inspectors more time before abandoning diplomacy.
They do not brief regularly during the war, but this week brought out a paper, Political Reconstruction in Iraq: A Reality Check, which argued that the US could not impose democracy in Iraq as if it were a blank slate and that other US actions in the Middle East would determine whether reconstruction would be a success.
Foreign policy experts on all sides of the debate are convinced that the shape of a new world order is being sketched out at the moment in Washington
But Carnegie is also the home to leading neo-conservative Robert Kagan who argues that Europe and America have irreconcilable differences over the use of force due to their history and culture.
Just across the street is another academic institution, the Johns Hopkins University School of Advanced International Studies, which was headed by the leading Pentagon hawk, Deputy Defence Secretary Paul Wolfowitz.
Now the dean of faculty is Francis Fukuyama, another foreign policy intellectual who ran the state department policy planning staff and argued that the Cold War had led to "an end to history" and the triumph of liberal democracy.
He is reserving judgement on the shape of the post-war order, but is clearly sceptical that it can be forged by US military power alone.
His colleague, however, Professor Elliot Cohen, believes that the Iraq war is the beginning of World War IV, the decisive conflict that will shape the 21st Century as the Cold War dominated the 20th Century.
Hawks and doves
The intellectual battles being fought in Washington are not merely idle chatter.
Foreign policy experts on all sides of the debate are convinced that the shape of a new world order is being sketched out at the moment in Washington.
And those who win the intellectual debate often find themselves serving in the government.
So whatever new paradigm becomes dominant, it will influence the conduct of US foreign policy for years to come, not just in the Middle East, but across the world.