By Matt Wells
As President Bush scurries back to the Gulf Coast, it is clear that this is the greatest challenge to politics-as-usual in America since the fall of Richard Nixon in the 1970s.
Then as now, good reporting lies at the heart of what is changing.
Mr Bush's famed "folksy" style has failed to impress in this crisis
But unlike Watergate, "Katrinagate" was public service journalism ruthlessly exposing the truth on a live and continuous basis.
Instead of secretive "Deep Throat" meetings in car-parks, cameras captured the immediate reality of what was happening at the New Orleans Convention Center, making a mockery of the stalling and excuses being put forward by those in power.
Amidst the horror, American broadcast journalism just might have grown its spine back, thanks to Katrina.
National politics reporters and anchors here come largely from the same race and class as the people they are supposed to be holding to account.
They live in the same suburbs, go to the same parties, and they are in debt to the same huge business interests.
Giant corporations own the networks, and Washington politicians rely on them and their executives to fund their re-election campaigns across the 50 states.
It is a perfect recipe for a timid and self-censoring journalistic culture that is no match for the masterfully aggressive spin-surgeons of the Bush administration.
'Lies or ignorance'
But last week the complacency stopped, and the moral indignation against inadequate government began to flow, from slick anchors who spend most of their time glued to desks in New York and Washington.
The most spectacular example came last Friday night on Fox News, the cable network that has become the darling of the Republican heartland.
Images of the military in a US city have shocked many Americans
This highly successful Murdoch-owned station sets itself up in opposition to the "mainstream liberal media elite".
But with the sick and the dying forced to sit in their own excrement behind him in New Orleans, its early-evening anchor Shepard Smith declared civil war against the studio-driven notion that the biggest problem was still stopping the looters.
On other networks like NBC, CNN and ABC it was the authority figures, who are so used to an easy ride at press conferences, that felt the full force of reporters finally determined to ditch the deference.
As the heads of the Homeland Security department and the Federal Emergency Management Agency (Fema) appeared for network interviews, their defensive remarks about where aid was arriving to, and when, were exposed immediately as either downright lies or breath-taking ignorance.
And you did not need a degree in journalism to know it either. Just watching TV for the previous few hours would have sufficed.
When the back-slapping president told the Fema boss on Friday morning that he was doing "a heck of a job" and spent most of his first live news conference in the stricken area praising all the politicians and chiefs who had failed so clearly, it beggared belief.
The president looked affronted when a reporter covering his Mississippi walkabout had the temerity to suggest that having a third of the National Guard from the affected states on duty in Iraq might be a factor.
It is something I suspect he is going to have to get used to from now on: the list of follow-up questions is too long to ignore or bury.
Thousands were forced to wait days for food and shelter
And it is not only on TV and radio where the gloves have come off.
The most artful supporter of the administration on the staff of the New York Times, columnist David Brooks, has also had enough.
He and others are calling the debacle the "anti 9-11": "The first rule of the social fabric - that in times of crisis you protect the vulnerable - was trampled," he wrote on Sunday.
"Leaving the poor in New Orleans was the moral equivalent of leaving the injured on the battlefield."
It is way too early to tell whether this really will become "Katrinagate" for President Bush, but how he and his huge retinue of politically-appointed bureaucrats react in the weeks ahead will be decisive.
Government has been thrown into disrepute, and many Americans have realised, for the first time, that the collapsed, rotten flood defences of New Orleans are a symbol of failed infrastructure across the nation.
Blaming the state and city officials, as the president is already trying to do over Katrina, will not wash.
Beyond the immediate challenge of re-housing the evacuees and getting 200,000-plus children into new schools, there will have to be a Katrina Commission, that a newly-emboldened media will scrutinise obsessively.
Black America will not forget the government failures, and nor will the Gulf Coast region
The dithering and incompetence that will be exposed will not spare the commander-in-chief, or the sunny, faith-based propaganda that he was still spouting as he left New Orleans airport last Friday, saying it was all going to turn out fine.
People were still trapped, hungry and dying on his watch, less than a mile away.
Black America will not forget the government failures, nor will the Gulf Coast region.
Tens of thousands of voters whose lives have been so devastated will cast their mid-term ballots in Texas next year - the president's adopted home state.
The final word belongs to the historic newspaper at the centre of the hurricane - The New Orleans Times-Picayune. At the weekend, this now-homeless institution published an open letter:
"We're angry, Mr President, and we'll be angry long after our beloved city and surrounding parishes have been pumped dry.
"Our people deserved rescuing. Many who could have been, were not. That's to the government's shame."