GULFPORT, Miss. - Judy Marsh sleeps in the back of her damaged Western clothing shop with a .380-caliber pistol at her side.
Like many business owners, she is dealing not only with storm damage but a looting free-for-all that has made shops like hers fair game.
Simple survival drives some to forage for essentials such as food and water. But others have used the opportunity for their own nefarious purposes.
They walk off with TVs, jewelry and guns. In parts of New Orleans, well-armed groups of men have shot at police. Even rescue helicopters have come under fire.
"Some people are just going out and looting because they can, because they want something for nothing," said Joe Spraggins, emergency management director in Mississippi's Harrison County. "But if someone is starving and they take some food, well, that's a life or death situation."
Katrina left many of the police agencies along Mississippi's coast in tatters.
Storm surge swept away the main headquarters in Gulfport. In Waveland, 14 police personnel clung to a bush for five hours after Katrina swamped their station.
The George County Sheriff's Office had 12 deputies to cover 400 square miles. The deputies were working 12-hour shifts, broken up by a few hours of sleep.
"We are working as many hours as we can stand," said Chief Deputy J.D. Mitchell.
Immediately after the storm, the overwhelmed agencies were forced to focus on saving lives, not property. Food, water and ice remained scarce and the power was down. The combination of circumstances hurled the affected areas into survival mode. Looters took advantage.
They descended on toppled casinos like vultures to a carcass. Convenience stores were wiped clean of beer. The front door of a rental car business in Biloxi was shattered, and keys were strewn everywhere.
"The President Casino has been looted, Toys "R' Us. It's just been ongoing all over the city," said Biloxi police Officer Michael Davis. The situation was worse in New Orleans.
Tensions began to boil over at the Superdome, where thousands took shelter. Looters set buildings on fire. Rescuers came under attack from storm victims.
"Hospitals are trying to evacuate," said Coast Guard Lt. Cmdr. Cheri Ben-Iesan. "At every one of them, there are reports that as the helicopters come in people are shooting at them. There are people just taking potshots at police and at helicopters, telling them, "You better come get my family."'
At a Rite-Aid pharmacy, thieves used a forklift to push up the storm shutters and break the glass. A woman on a bicycle rode up Thursday and asked whether police were making arrests.
Told no, she said, "I'm a diabetic. I need test strips. I'm down to two. I don't know if my insulin's any good. It hasn't been on ice."
Earl Baker walked out carrying toothpaste, toothbrushes and mouthwash.
"All of this is personal hygiene," he said. "I ain't getting nothing to get drunk or high with."
Rules of human behavior often are no match against overwhelming desperation, according to social psychologists.
Parts of the affected areas have regressed into what ethicists call the state of nature - an environment where survival trumps rules or common decency.
"It isn't that it justifies it," said Jan Boxill, associate director of the Parr Center for Ethics at the University of North Carolina. "But where there's no laws that can help anybody, one way or the other, obviously people need what they need to survive."
Officials hoped Thursday that a mass influx of National Guard troops and out-of-state law officers will restore order. The National Guard had set up checkpoints to help enforce local curfews.
Water and ice also began to flow into many areas, which should alleviate some of the desperation.
Marsh was ready just in case.
"This is the South," Marsh said. "It's not just the criminals that have guns."
This report includes information from the Associated Press, New Orleans Times Picayune, the Jackson Clarion-Ledger and Biloxi Sun-Herald.