Funding for flood prevention was slashed by 80 per cent, work on strengthening levees to protect the city was stopped for the first time in 37 years, and planning for housing stranded citizens and evacuating refugees from the Superdome were crippled. Yet the administration had been warned repeatedly of the dangers by its own officials.
In early 2001, at the start of Mr Bush's presidency, his Government's Federal Emergency Management Agency (Fema) warned that a hurricane hitting New Orleans would be the deadliest of the three most likely catastrophes facing America; the others were a massive San Francisco earthquake and, prophetically, a terrorist attack on New York.
Fema's then director, the Bush appointee Joe Allbaugh, said that the warning caused him "great concern". But the President emasculated the agency, subsuming it into the Department of Homeland Security set up after the 11 September 2001 attacks, which concentrated on the terrorist threat.
This was only one of a series of warnings that predicted what happened last week, including the storm surges brought by the hurricane, the breaching of the levees, the floods covering the city, and the "toxic gumbo" of sewage, oil and chemicals.
Last year an emergency exercise run by the federal, Louisiana and New Orleans governments, featuring a fictional Hurricane Pam, almost exactly foretold the disaster now unfolding. But officials said plans to prepare for an actual catastrophe were abandoned because of cuts. Three years ago, another study concluded that a hurricane less intense than the one that has now hit New Orleans would flood most of the city; in 1998 a less severe one still, Georges, produced a 17ft wall of water.
"No one can say they did not see it coming," reported the The Times-Picayune from New Orleans this week. The newspaper published a five-part series predicting the disaster five years ago. Officials and experts last week wearily recalled their attempts to make the government take action. "It's frustrating to have planned, begged and pleaded that this could happen," said Walter Maestri, emergency management director of the now submerged Jefferson Parish. "They would say, 'Yeah, yeah, yeah.' Well it's here now."
Warnings stressed the inability of levees to resist a storm surge and the city's increasing vulnerability because of the destruction of natural defences. New Orleans is surrounded by 350 miles of levees - often flat, grass-covered embankments with parks and bicycle tracks - that were built soon after the city was founded in 1718. But tests have shown they are too low to withstand the water whipped up by even a category three hurricane, let alone a category four like Katrina. The levee at the 17th Street Canal, where the crucial breach took place, was particularly vulnerable, with part of it four feet lower than the rest.
Every four miles of marsh shrinks the storm surge by a foot. But the city has become more defenceless as the wetlands that protected it against the sea vanished at a rate of 25 square miles a year - that's one football field every quarter of an hour. The oil and gas industry has caused much of this loss, as have the levees themselves by flushing silt out to sea that used to replenish the Mississippi Delta. While the surges have risen, the city has sunk two feet in the past 60 years.
Natural and man-made defences have long been neglected. A 10-year plan to strengthen levees after a 1965 hurricane was never completed. But the skimping has worsened since President Bush's election, particularly after 11 September. Federal spending on flood control in south-east Louisiana has been cut by almost half since 2001, from $69m (£34.5m) per year to $36.5m. Funds for work at Lake Pontchartrain, the source of the flooding, have fallen by nearly two-thirds over three years, from $14.25m to $5.7m. As a result, work on New Orleans' east bank hurricane levees stopped last summer for the first time in 37 years.
The US Army Corps of Engineers, which maintains the levees, requested $27m this year for hurricane protection around the lake. President Bush tried to cut this to $3.9m, although Congress allowed $5.7m. The President also tried to cut $78m to improve drainage and prevent flooding in the city to $30m, though Congress passed $36.5m. A $14bn longer-term project to restore marshes was cut to $570m.
Plans to provide shelter for victims and evacuate the Superdome, started after last year's Hurricane Pam exercise, were abandoned. Eric Tolbert, chief of disaster response at Fema until last February, said this was because funding dried up. "What you are seeing is revealing weaknesses in the state, local and federal levels," he said last week. "They have been weakened by diversion into terrorism."
Mr Maestri, the Jefferson Parish emergency director, added: "It appears that money has been moved in the President's budget to handle homeland security and the war in Iraq. I suppose that's the price we pay."