NEW ORLEANS — Since Hurricane Katrina hit, the Oklahoma National Guard’s 45th Infantry Brigade waited for an order that never came — force the evacuation of New Orleans.

Now, about two weeks into the disaster that flooded 80 percent of the city, rendering those parts uninhabitable, the Thunderbirds have altered their plans to carry out such orders and instead focus on other priorities in the mission — supporting, securing and rendering aid.

Operating from the parking lot of the looted Wal-Mart Supercenter on Tchoupitoulas Street in the Crescent City’s Garden District, the 45th patrols the area, conducts reconnaissance along the edge of the flooded portions, deters or arrests looters and provides assistance to residents who stayed, instead of forcing them out at gunpoint.

“Initially our mission was to cordon off our area and assist in the evacuation of the city of New Orleans,” said Maj. James Gill, the “battle major” of the 45th’s headquarters, in charge of the detailed directing of units involved in the effort. “Since the governor of Louisiana did not sign the order for the forced evacuation, our mission is to assist the local population and the local government.”

Gill said he is unable to estimate how many hundreds of people were evacuated by elements of the 45th. He said 36 bodies have been marked for removal from the areas under the 45th’s control, but said many more are likely submerged outside of the Thunderbirds’ patrol sectors.

The Thunderbirds, under the command of Brig. Gen. Myles Deering, assumed command of Task Force New Orleans, the largest unit operating in the city’s rescue efforts. The task force consists of 14,000 troops, including more than 2,000 of Oklahoma’s 45th. Part of the 45th’s duties includes patrol of the Garden District, some of the most expensive real estate in the United States. Most older, affluent areas of the Garden District did not flood but remained vulnerable to looters or vandals.

Armed with loaded M-16s, soldiers from Tulsa, Ada, Norman, Kellyville, Catoosa and other Oklahoma towns regularly stroll past antebellum homes worth millions, scouting for looters.

The streets are eerily quiet. No light shines from the colonnades of mansions lining the streets. On one street sits the mansion where Confederate President Jefferson Davis died. On another lies the former home of vampire novelist Anne Rice. On yet another is the home of Nicolas Cage, a vacant limousine sitting next to it unused. Not a sound comes from the homes except for the wail of a lonely house cat, the fading beep of a dying smoke alarm, or the rush of a broken water pipe or faucet, running again now that the water is turned back on. The older homes appear mostly undamaged, perhaps built at a time when unexpected hurricanes were a forethought.

As patrols come back from night, other units ready themselves in the Wal-Mart parking lot by sunrise, filing in formation against the backdrop of the darkened Garden District. Helicopters whir overhead, on their way to pick up evacuees or towing a massive orange water bucket to a fire in the distance. In a vacant field next to where the soldiers call roll, a flock of some kind of parakeets, with green feathers and blue wings, perhaps released from a pet shop, scratch and pick in the grass.

“I’ve never seen such a big ghost town in my entire life,” said 1st Lt. Eric Kennedy.

One of the detachments that make up the Thunderbirds made its headquarters in the rotunda of a hotel on St. Charles Avenue. Most of the rotunda’s massive windows are blasted out from the hurricane.

The streetcar that trolls St. Charles on its way to and from the French Quarter is absent, stowed when the hurricane hit. The streetcar’s tracks are littered with fallen debris. The traffic lights, some dangling crazily, do not work. Emergency and military vehicles speed along the street, careful to avoid one another.

Near the Audubon Zoo, at the end of Magazine Street, the 179th is camped. Soldiers fulfill many of their tasks with golf carts from the nearby golf course. There, helicopters regularly take off and land, using the open area of the course for staging medevac, reconnaissance or rescue missions.

For those who venture outside the Garden District, the devastation is incredible. Many of the poorer neighborhoods, such as those in nearby St. Bernard Parish, remain mostly underwater.

Sgt. Rocky Seals of Catoosa said the loss is overwhelming.

“You have to be a soldier, but you still have a heart,” Seals said. “You can’t put into words the devastation. What you see on TV ain’t half of it.”

In Vietnam, Seals said he took part in the fighting during the Tet offensive, making him perhaps one of the oldest soldiers in the Thunderbirds.

“Let’s just say I thought I’d seen everything, but this is the worst,” Seals said. “This is part of our family. This is your own land, your own brothers and sisters.”