"This is one of the worst national disasters we have faced, with national consequences and there will be a national response," Mr Bush said as he arrived in New Orleans, having completed a tour of the devastated cities of Mobile, Alabama, and Biloxi on the Mississippi Gulf coast.
But the news continued to get worse, with explosions rocking the industrial area of the city and fires breaking out throughout the region. The estimated death toll in Louisiana alone is now exceeding 10,000.
Having noted during the tour that Congress had approved a $10.5bn (£5.8bn) aid package for the three-state region, in his televised statement Mr Bush appealed to viewers to send contributions in cash to the American Red Cross and the Salvation Army.
There is little chance that his visit, a full five days after the storm struck, will have the same tonic effect on Mr Bush's fortunes as his trip to the smouldering Ground Zero in New York after the 11 September attacks regarded as the high point of his presidency, in which an entire country united behind him.
A country still struggling to grasp the dimensions of the catastrophe had been stunned by the outburst of Ray Nagin, the New Orleans mayor, voicing the fury, the frustration and sense of helplessness of those waiting to be evacuated. "Get off your asses and let's do something," he said in an emotional interview with a local radio station. "I need reinforcements, I need troops, man. This is a major, major deal." He later added: "Excuse my French, everybody in America, but I am pissed [fed up]."
Later the mayor, who accompanied Mr Bush on his tour, described how in the city's convention centre, which is being used as a refuge, 100 police officers were shot at on Thursday night. They chose to leave rather than return fire, for fear of hitting innocent people sheltering there in the darkness.
"I continue to hear that troops are on the way, but we are still continuing to protect the city with 1,500 National Guardsmen," Mr Nagin complained, challenging government claims that 30,000 guardsmen were on hand. He estimated that 50,000 people were still trapped in the city, thousands of whom would die unless relief arrived immediately.
Last night the National Guard arrived in force with food, water and weapons, churning through the floodwaters in a vast truck convoy with orders to retake the streets and bring relief to the suffering. At the New Orleans Convention Centre, some of the thousands of people awaiting their deliverance applauded, threw their hands skywards and screamed, "Thank you, Jesus!" as the camouflage-green trucks and hundreds of soldiers arrived.
America's old racial demons have been reawakened by the crisis unfolding in a city that is 67 per cent black, and where almost a third of the population already lived below the poverty level. As the emergency aid was being approved on Capitol Hill, a seething congressional black caucus demanded a far stronger response from the federal government. "Let not it be said that the difference between those who lived and those who died was poverty, age and skin colour," said Elijah Cummings, a Maryland representative.
The President insisted he was doing all he could, Mr Cummings said, " but I simply disagree. We heard the campaign slogan of 'compassionate conservatism'. We now want some compassion."
Other black congressmen drew scathing comparisons with the Iraq war, on which the US now spends more than $5bn a month. "They talked of 'shock and awe' in Iraq," said Jesse Jackson Jnr, an Illinois representative and son of the civil rights leader. In New Orleans, "we have witnessed the shockingly awful".
Even before Katrina, Mr Bush's ratings were at a record low. Now, from elements on the right, as well as the left, the White House has faced a barrage of criticism that the government has done far too little, too late.
Even the staunchly conservative Washington Times weighed in against Mr Bush. "We're pleased he finally caught a ride home from his vacation," the paper declared. But it was "time to crack heads," it wrote. Otherwise "he risks losing the one trait his critics have never dented, his ability to lead."
Mr Bush is blamed for downgrading the Federal Emergency Management Agency, for neglecting years of warnings about a potential hurricane calamity in New Orleans, and of failing to understand the magnitude of the crisis. The mantra of this president as he defends the "war on terror" is that the priority of his job is to keep the country safe. Yet the anarchy and violence in New Orleans show he is failing in that task.
The day the Mayor's patience ran out
'I told him [George Bush] we had an incredible crisis here and that his flying over in Air Force One does not do it justice.
I have no idea what they [George Bush and the Louisiana Governor, Kathleen Blanco] are doing. But I will tell you this: you know, God is looking down on all this and if they are not doing everything in their power to save people, they are going to pay the price.
I don't know whose
problem it is. I don't know whether it's the Governor's problem. I don't know whether it's the President's problem. But somebody needs to get their ass on a plane and sit down, the two of them, and figure this out right now.' - Ray Nagin, Mayor of New OrleansReuse content