As its effects unspool throughout the nation, hurricane Katrina now seems likely to enter US history as an iconic disaster on the level of the Chicago fire of 1871, the San Francisco earthquake of 1906, and the Mississippi flood of 1927.
New Orleans and other hard-hit areas are struggling just to reestablish normal bonds of society. Gunfire disrupted initial attempts to evacuate refugees from the Superdome on Thursday. In Baton Rouge, La., armed men hijacked a nursing-home bus, evidence of the looting continuing in the region.
Elsewhere, Americans saw the hurricane's winds in the swiftly rising numbers on gas station signs. The price of other commodities may well rise, as the lower Mississippi is a great funnel through which vast amounts of goods flow. New Orleans is a major port for grains, coffee, and other bulk items. Fruit giant Chiquita Brands routes one-quarter of its fresh bananas through the area, for instance.
Looking forward, residents and officials face rebuilding one of the most unique cities in the United States, if not the world. The challenge will be to maintain New Orleans's character while trying to improve the levees and pumps that served as bulwarks for so long.
"This is the largest disaster the US has perhaps ever seen, in terms of its scope, its breadth," says Tiziana Dearing, a relief expert and director of Harvard University's Hauser Center for Nonprofit Organizations.
As unbelievable as it may seem in a nation with no rival for wealth and military power, the extent of the Katrina disaster remains unclear days after the furious winds had passed. At press time, there were 110 confirmed fatalities in Mississippi, and Louisiana officials said the final death toll there could number in the thousands. If so, Katrina would rank as one of the deadliest US natural disasters.
The 1906 San Francisco earthquake killed perhaps as many as 6,000 people. The 1900 Galveston hurricane resulted in upwards of 12,000 fatalities.
About 2.3 million people remained without power in a swath from Louisiana to Georgia. New Orleans was under martial law, with residents ordered to evacuate. Officials estimate the city will not be habitable for months, raising the eerie prospect of an American metropolis lying empty for a significant amount of time.
"We are really dealing with an extraordinarily unusual and unique situation," says Walt Peacock, director of the Hazards Reduction and Recovery Center at Texas A&M University. "We now have 500,000 people displaced."
While some corporations say will continue to pay their displaced employees, this vast army of refugees will now sit on the edges of the affected region and look for things to do, says Mr. Peacock. They will face everyday problems of feeding and educating children, finding housing, and making money.
The question is, will they ever move back? "In most disasters, there is an invisible population of the lower income that simply move off to another area.... Here we're dealing with a broad spectrum of people being forced out," says Peacock.
In Washington, the White House said President Bush will tour the devastated region Friday, and has asked his father, former President George H.W. Bush, and former President Clinton to lead a private fundraising campaign for victims.
The president urged a crackdown on the looting and other lawlessness that have spread through New Orleans. Fights and trash fires marred the exodus from the Superdome, in addition to the shots and brandished guns that halted ambulance service and evacuation convoys Thursday.
"I think there ought to be zero tolerance of people breaking the law during an emergency such as this - whether it be looting or price gouging at the gasoline pump," said Mr. Bush.
Price gouging, or the appearance thereof, is much on the mind of many people. "Out of Gas" signs were draped across pumps in parts of the nation Thursday after many retailers were overrun by panicked motorists looking to top off their tanks.
The nation's refineries were operating 11 percent off their regular capacity - some 1.8 million barrels a day short. The LOOP, or Louisiana Offshore Oil Port, remained closed. But a release from the strategic oil reserve, located in the Gulf, was expected to reach refineries Thursday.
In Vermont, legislators called for more oil to be released, as $3-a-gallon gasoline became a norm. In Atlanta, $6 gas was seen, and in Tennessee, South Carolina, and Maryland, independent operators and franchisees began worrying about supply, and even rationing. In Georgia, Gov. Sonny Perdue said he would punish gas gougers.
"We have a serious refinery problem," says Adam Sieminski, chief energy economist at Deutsche Bank AG.
While gouging may be occurring in some places, experts say America is experiencing a natural supply and demand problem that is not likely to need rationing to resolve. As power comes back on with the next few days, refineries and pipelines will resume operations.
High prices are not by themselves signs of gouging. Vince Datillio, owner of a gas station and gun shop in South Burlington, Vt., has raised prices 53 cents, to $3.12. But his profit margin remains the same. "I make a nickel a gallon," he says.
The future holds massive rebuilding - and with it, an opportunity to try to prevent a repeat of this week's disaster. Given this storm surge, a record 27 feet in places, perhaps no system of levees could have remained undamaged.
"We need to balance the technology and engineering with making smart development land-use decisions," says Samuel Brody at the Hazards Reduction and Recovery Center at Texas A&M.
• Adam Karlin contributed to this report.