Bush first stopped at the Bethany World Prayer Centre, a huge hall half-filled with dining tables. Louisiana governor Kathleen Blanco, a Democrat, visited at the same time, but she and the Republican president kept their distance as they walked around talking to people.
At the second stop - a visit to an emergency operations centre - Bush kissed Blanco on the cheek, but it was not clear whether they had made up. The two said little publicly during the appearance.
"I know I do not need to make any other introduction other than 'Mr President'," Blanco said tersely, turning the microphone over to Bush after thanking emergency workers for their hard work.
Bush echoed Blanco's praise for rescue workers. "I hope that makes you feel good to know you have saved lives," Bush said, promising state, local and federal officials that he would fix anything not going right.
"This is just the beginning of a huge effort," he said. Behind the scenes, state and federal officials - all facing public criticism for a slow response to the crisis - have each suggested the other is to blame.
Myriona Bentley, 13, is displaced
from New Orleans
Blanco has refused to sign over National Guard control to the federal government and has turned to a Clinton administration official, former Federal Emergency Management Agency chief James Lee Witt, to help run relief efforts.
Blanco was not informed of the timing of Bush's visit, nor was she immediately invited to meet him or travel with him. Blanco's office did not know Bush was coming until told by an Associated Press reporter.
Bush spokesman Scott McClellan said the White House reached out to Blanco's office on Sunday but did not hear back, and White House staff in Louisiana spoke with Blanco early on Monday.
During his stop at Bethany, several people ran up to meet Bush as he and First Lady Laura Bush wandered around the room. But just as many hung back and just looked on.
"I am not star-struck. I need answers," said Mildred Brown, who had been there since Tuesday with her husband, mother-in-law and cousin.
"I'm not interested in hand-shaking. I'm not interested in photo ops. This is going to take a lot of money."
Nothing Bush or his cabinet has done has quieted complaints that Washington's response to the disaster has been sluggish.
Aaron Broussard, president of Jefferson Parish, just south of New Orleans, sobbed on Sunday on NBC's Meet the Press when he talked about people who waited for help.
Two women are rescued by a US
Navy helicopter in New Orleans
"They were told like me, every single day, the cavalry's coming, on a federal level," Broussard said. "I have just begun to hear the hoofs of the cavalry."
Meanwhile, Russ Knocke, a spokesman for the Department of Homeland Security, said the number of people rescued has reached 22,800, more than four times the number the Coast Guard usually saves in a year.
At least 273,000 people have been evacuated from the stricken areas and sheltered in 16 US states with most housed in about 560 shelters.
More than 60,000 civilian and military personnel were providing assistance in the stricken area.
It was Bush's third inspection tour, the second on the ground.
Last week, he had his pilot lower Air Force One, the presidential jet, to an altitude of about 762m as he flew over the area.
On Friday, he walked a neighbourhood in Biloxi on Mississippi's coast and stopped at the airport and a breached levee in New Orleans.
A Mississippi resident carries
dishes found near her home
By contrast, Baton Rouge, northwest of New Orleans, largely escaped damage. Its population, however, has swelled dramatically with displaced people and is experiencing clogged roads and supply shortages."We're here for the long term."
In the afternoon, Bush visited Poplarville, Mississippi, to meet Republican governor Haley Barbour and other state and local officials at the Pearl River Community College.
The city is about 70km inland, but the area was in the path of Katrina's eye and devastation in the town and surrounding rural areas was enormous.
"I just want you to know that when I am thinking about how we can help this part of the world, Mississippi is on my mind," Bush told the crowd gathered at the college.
In Houston earlier on Monday, former presidents George Bush Sr and Bill Clinton announced a nationwide fund-raising campaign to help the hurricane victims.
"I am not star-struck. I need answers"
Bush has come under fire for waiting until two days after Katrina hit - and a day after levee breaks drowned New Orleans and turned it into a place of lawless misery - to return to Washington from his August break in Texas to oversee the federal response.
It took several days for food and water to reach the tens of thousands of desperate New Orleans residents who took shelter in the increasingly squalid and deadly Superdome and City Convention Centre.
Outlying areas, though receiving less nationwide attention, suffered some of the same problems. Officials are now reporting some progress and some new worries.
Hundreds of federal health officers and nearly 100 tonnes of medical supplies were on their way to the Gulf Coast to try to head off disease outbreaks, feared because of the hot weather, mosquitoes and standing water holding human waste, corpses and other contaminants.