As the cheering echoes through the streets of Baghdad, the conflict in Iraq is entering the crucial next phase - a subtle and shifting mix of urban fighting, police work, and helping Iraqis live in their war-torn land. It is likely to take many months, cost much more than the three-week war has so far, and could well require thousands more coalition troops.
The euphemism "nation building" applies. But even the occupation necessary to precede a transition to self-government will take at least six months, according to Deputy Defense Secretary Paul Wolfowitz, one of the Bush administration's head cheerleaders for regime change. And it may turn out that Army Chief of Staff Gen. Eric Shinseki was right in his public dispute with Mr. Wolfowitz, when he said that it could take at least 200,000 troops to do the job. (Some 125,000 are there now.)
Retired Gen. Charles Krulak, former commandant of the Marine Corps, calls what's coming now the "the three-block war."
"In one moment in time, our service members will be feeding and clothing displaced refugees - providing humanitarian assistance," he says. "In the next moment, they will be holding two warring tribes apart - conducting peacekeeping operations. Finally, they will be fighting a highly lethal mid-intensity battle. All within three city blocks."
In Baghdad and other cities as well, there remain pockets of resistance by loyalists and non-Iraqi Arab militants. Widespread looting may just be an expression of jubilation, as US Central Command briefers said Wednesday, or a sign of more criminality to come during a period of lawlessness. And some Iraqis may want to seek their own form of justice for a lifetime of political repression and abuse.
"If it has not already started, there will be revenge attacks on Baath Party functionaries, intelligence and special-security-organization goons, and fedayeen fighters, plus the inevitable score-settling that has nothing to do with Saddam," says retired Army Col. Dan Smith. "Add the thousands of small arms that abound in Iraq, and keeping the peace will be a challenge."
At the moment, Colonel Smith, adds, "There are too few troops to control the disorder or maintain the peace."
Haiti, Bosnia, and Afghanistan have provided hard lessons and some experience in such warfare, but nothing on the scale likely to be seen in Iraq. Army and Marine Corps troops have had some training, but not enough, most experts agree. In any case, three hard weeks of combat means many of those troops will have to be rotated to rear areas (or back to the United States), likely to be replaced and augmented by fresh troops from the Army's recently arrived 4th Infantry Division.
But even fresh troops, including a large contingent of civil- affairs specialists, will not have an easy time of it. And at some point, according to observers, it may be that a broader coalition under United Nations auspices is called for.
"As long as US troops are responsible for peacekeeping and humanitarian aid, any little thing that goes wrong will be blamed on the US," says Charles Peña of the Cato Institute in Washington. "That could have a lasting impact on the ability of the US to implement the peace."
"Lebanon and Somalia are examples of what can happen when things start to go wrong," adds Mr. Peña. "However well-intentioned the US might be, we could get caught in the crossfire."
Meanwhile, the need for humanitarian aid grows daily. Most Iraqis have been getting their food in the form of rations from the government, paid for under the UN's oil-for-food program. But government ministries have collapsed with the regime, and some food rations are running out.
Electricity in Baghdad has been out for a week. The International Committee of the Red Cross reports that one of the water plants in Baghdad was bombed. This plant, the ICRC acknowledges, may have been "dual use" - serving both military and civilian needs - and therefore a legitimate military target. In any case, that still leaves many people without fresh water.
Such problems are found across the country.
Central Command has talked about restoring electricity and water in southern Iraq. But even saying it this way makes it clear that they do not understand the problem, says retired Air Force Col. Sam Gardiner.
"There was almost nothing to restore," says Colonel Gardiner. "Some water plants near Basra before the war were only getting two hours of electricity [a day]. The electrical grid was very fragile and only 50 percent of what it was in 1990" just before the last Gulf War.
This phase in the war is likely to illustrate the importance of the "strategic corporal," General Krulak's term for the junior soldier or marine who is likely to find himself faced with deciding which phase of the three-block war he's in as he encounters Iraqis.
"The behavior and decisions of even the most junior leaders and soldiers can percolate up to affect national policy," says Mark Burgess, a military analyst with the Center for Defense Information in Washington who previously served with the British Army in Northern Ireland.
A taste of that happened Wednesday when - to the consternation of those in the Pentagon watching the event on live television - US marines put an American flag atop a statue of Saddam Hussein. To many Iraqis gathered in the streets of Baghdad, that was a symbol of occupation. An Iraqi flag quickly replaced it.