But beyond the destruction and human misery, something else is starting to become clear. Like the September 11 attacks on New York and Washington, whose fourth anniversary is this weekend, Hurricane Katrina is an event whose consequences will extend far beyond the physical, into the very mind of America.
This is a country where savage acts of nature have a way of unleashing massive social and political change. The Great Mississippi flood of 1927 exposed the deep iniquities of the post-Civil War South, and accelerated the historic internal migration of blacks to the industrial cities of the north.
The calamitous Johnstown flood of 1889 killed 2,200 and started the backlash against greedy "robber baron" industrialists whom public opinion deemed indirectly responsible. And in a different way, the legacy of Katrina may be no less momentous and far-reaching.
The immediate victims are the central US Gulf Coast, and the submerged city of New Orleans. The city will be rebuilt; its tourist attractions, have for the most part, survived relatively unscathed. Sadly, but almost certainly, the city will arise but a shadow of its former self.
Cities on the rise can overcome natural disasters. Chicago and San Francisco shrugged off apocalypses - one by fire, the other by earthquake - to flourish as never before. But New Orleans is different. The seductive, raffish fatalism of the place was the mask of a city in long decline, notorious for its appalling civic government, its corruption, its deep divisions of wealth, class and race.
But Katrina's aftershocks will ripple far beyond the South. The storm is likely to alter the way in which the rest of the world regards the planet's lone, but suddenly vulnerable superpower, and more important, how America regards itself and its long-dominant political ideology.
For a quarter of a century, libertarianism has run riot in the US, since Ronald Reagan rode into town proclaiming that government was not the solution, but the problem. George Bush the elder had his doubts, but was forced by the right to embrace the mantra of "no new taxes". Ultimately he had to abandon it, and lost the White House to Bill Clinton. But for all his gifts of empathy, Clinton the New Democrat did not seriously depart from the philosophy. Under this George Bush it has reached its apogee.
Since 2001, the only branch of the federal government that has really been beefed up is the military. Tax cuts have proceeded headlong; spending on many other core functions of government has been reduced.
This President likes God but does not much like government. Katrina and its aftermath have utterly exposed the limits of that approach. Leave aside where hurricanes fit into a universe shaped by intelligent design. This was the most widely predicted natural disaster in American history, a matter of when, not if.
Yet, the administration was pitifully unprepared. For the first week, Mr Bush unfailingly struck the wrong note. On their visits to the stricken region, he and Vice President Dick Cheney and Donald Rumsfeld the Defence Secretary, have given the impression of corporate bosses inspecting damaged plant at a poorly performing subsidiary.
The Republican-run federal government has been found wanting; but so too have the state and city administrations in Louisiana and New Orleans, both in Democratic hands. But a deeper reason is at play as well. If you spend 25 years denigrating government, you should not be surprised that this same government, weakened and demoralised, fails to deliver when it is needed. For this President, there is no problem that cannot be solved by faith, hope and charity, and as he likes to say, by "the innate goodness of the American people". But the corollary is that the less fortunate in society must pull themselves up by their boot straps. Look not to your government, in other words, but to yourself and your Maker.
But as Katrina has demonstrated, "compassionate conservatism" can achieve only so much. The abiding lesson of this crisis is that, in the end, there is no substitute for a honed and efficient central government. For decades, Grover Norquist, among the most powerful figures in Washington's conservative establishment, has been seeking to diminish government to the point where he could "drown it in the bathtub". His wish has come true, except that the bathtub is New Orleans, drowned because of breaches in the protective levees that the government failed to properly repair.
Katrina may prove a pivotal moment for American politics and American society. Doctrinal minimalist conservativism has run its course. The pendulum is poised to swing back to more activist government.
The Bush crowd may be counted upon to resist such changes. Within months he will be pushing Congress back to an agenda of tax cuts as usual. This President cannot admit to error. Astonishingly, at the time of writing, he has not appointed a "recovery czar", say, Colin Powell the former secretary of state
If ever there was a moment for America to show itself the "humble nation" that President Bush so mendaciously promised in 2000, this is it. But humility is not in this administration's gene pool. Its nature is to lecture and lord it over others. Even Katrina, which turned a major American city into Mogadishu and laid bare the shameful divisions of wealth, class and colour in the US for all the world to see, is unlikely to dent its sense of righteousness in its foreign policy.
But reality cannot forever be denied, even by this White House which for so long has lived in a universe in which everything is going swimmingly in Iraq, where tax cuts answer all problems, and where global warming does not exist. Katrina, and the initial shambolic response of the government to the calamity, have changed everything.
For the world, US preaching, US leadership, even US powerring hollow. Back home, a quarter-century era of anti-government is surely coming to an end. President Bush could rise to the occasion by recognising this.
More probably he will not. So then he will spend out his time in office as the lamest of lame ducks, disavowed even by those in his party who realise that his way of doing things does not work. And whoever comes up with a way that works better - he (or she), Republican or Democrat - will be the next president.Reuse content