Water stands in much of the area around downtown New Orleans seven days after Hurricane Katrina devastated the city on Sept. 5, 2005. Hurricane Katrina hit the Gulf Coast on Aug. 29, 2005, battering New Orleans, swamping towns and lowlands with seawater and stranding people on rooftops.

Twenty years later, Edward Buckles Jr. remembers Katrina − remembers at age 13 having his neighborhood swept away by the hurricane's raging waters, a defining moment of his life that would dislodge his family for a time from its New Orleans roots.

Twenty years later, America remembers Katrina, too − remembers one of the deadliest natural disasters in modern U.S. history, raising questions that persist today about the crises of climate, the role of government and the nation's divides by race and class.

In a new USA TODAY/Ipsos Poll, 85% of Americans said they were familiar with Hurricane Katrina despite the passage of two tumultuous decades packed with competing news events, from an economic meltdown to wars abroad to a global pandemic.

"The images are just burned into people's minds and hearts and souls about what those days and weeks looked like with the city underwater," said Mary Landrieu, then a Democratic senator from Louisiana, the daughter of one New Orleans mayor and the sister of another. "The thousands of people that were stranded at the Superdome − I mean, that was a catastrophe and a real failure of the local, state and federal government."

As the hurricane approached, she and her extended family fled their summer camp on Lake Pontchartrain. Hours later, "it was destroyed," she said in an interview. "There wasn't a stick or a stone left."

The most intense memories are understandably in the South, where scars from the storm's battering can still sometimes be seen.

But the imprint of Katrina also remains remarkably wide across the country, recalled by nearly 9 of 10 in the Northeast and more than 8 in 10 in the Midwest and the West.

Even among those now 18 to 34 years old − no more than teenagers when the storm struck, and some not even yet born − three-quarters say they know at least a little and sometimes a lot about the tropical cyclone that in August 2005 left devastation in its wake across Louisiana, Mississippi and Alabama.

Nearly everyone surveyed said the storm had a negative impact on New Orleans; 3 of 4 described the harm it did as significant.

Hurricane Katrina is believed to have killed 1,392 people − the deadliest hurricane since the Okeechobee hurricane in 1928 − and to have caused an estimated $200 billion in damage, when adjusted for inflation, one of the costliest storms to ever hit the United States.

When disasters strike, who should help?

One reason Americans may remember Katrina is that its story isn't really over, that the issues it ignited haven't been settled.

"Katrina was a canary in the coal mine," said Maurice Carlos Ruffin, now an award-winning novelist and professor at Louisiana State University but then a young professional who lost his house, job and car in the storm. It spotlighted what many saw as government incompetence or disregard for those who were poor and people of color.

Among the issues that still resonate today:

What should be done before the next storm?

Eight in 10 said Katrina showed the nation's disaster preparedness needs to be improved. Nearly as many, 73%, said it demonstrated a need to invest more in infrastructure in vulnerable coastal areas.

Katrina was not only a natural disaster but also a man-made one. The death toll was exacerbated because the levees in New Orleans were breached, a failure blamed afterward on engineering flaws and cost-saving measures by the U.S. Army Corps of Engineers when they were built.

Who should help after disaster strikes?

A large majority of Americans endorsed major roles for the federal government (71%), state governments (83%) and local governments (79%), but less so for the private sector (38%). About 66% called the services from of the Federal Emergency Management Agency "very necessary" and 57% supported increasing its budget.

But FEMA is now under fire by the Trump administration, its future uncertain. President Donald Trump has said he wants to phase out FEMA after the current hurricane season ends in November, cutting its funding and transferring most of its responsibilities to the states.

Despite the significant support for FEMA, Trump's proposal strikes a chord with the public in some ways. Americans were skeptical about the ability of any level of government to handle major natural disasters, but their confidence was higher in state and local government (48% and 49%, respectively) than in the federal government (30%).

Even lower was their confidence that Washington has learned the lessons of Katrina. Just 22% predicted the federal response would be better if a storm like Katrina hit again.

Should people just live someplace less perilous?

There was no consensus on just how much help the government should give to people who live in areas known to be especially susceptible to landslides, earthquakes, hurricanes and flooding: 40% said residents should live at their own risk; 35% said the government should help them recover if disaster strikes.

No surprise that views of the role of government reflect the nation's partisan divide. Democrats by 2-1 supported government help; Republicans by 2-1 said residents in at-risk areas should be on their own.

Are weather disasters getting worse?

Most Americans said extreme weather has gotten more frequent and more intense over the past 10 years in the places they live. A third said they worry, occasionally or frequently, about becoming a victim of a disaster like a hurricane, tornado or earthquake.

By 3-1, those surveyed said humans could slow or reverse climate change but aren't willing to change their behavior to do that. Nearly 1 in 5 thought progress was being made; 1 in 5 said it's already too late.

The online poll of 1,023 adults, taken June 13-15 using Ipsos KnowledgePanel, has an error margin of plus or minus 3.2 percentage points.

Dividing life into Before-Katrina and After-Katrina

For some, the legacy of Katrina is personal, not policy.

"There's an argument where New Orleans has bounced back fully, if you're looking at it from the perspective of tourism or if you're looking at it from the perspective of business, right?" said Buckles, a filmmaker who produced "Katrina Babies," an HBO documentary about the storm's impact on the children who lived through it. "But I think that it's those things that you really can't see − the mental health trauma − that is still surfacing."

Many of those he profiled said the lesson they learned was that neither the federal government nor the local police nor anyone else could be counted on to rescue them when catastrophe struck. Some describe their lives as divided into Before-Katrina and After-Katrina.

"It's constantly in our daily conversation," Buckles said. "It's like we can barely talk about anything without mentioning Katrina."

In the nationwide poll, a 58% majority said Katrina showed that race and economic status can help determine who gets hurt by a natural disaster, and by how much.

Among White and Hispanic respondents, that was the view by 3-1. Among Black respondents, that opinion was held by nearly 6-1, 61%-11%.

In modern times, a handful of images have become iconic, defining a moment in history and recognizable in a flash: For the Vietnam War, a naked girl fleeing a napalm attack. For the Civil Rights Movement, Alabama troopers lifting truncheons to beat marchers crossing Selma's Edmund Pettus Bridge. For 9/11, three New York City firefighters raising an American flag amid the wreckage of the World Trade Center.

Some of the images from Katrina have been indelible, too − of desperate people trapped for days on their roofs or in their attics to get above the floodwaters and of thousands taking chaotic refuge in the Superdome. Of President George W. Bush, flying overhead on Air Force One, peering out a window at the devastation a mile below.

Exclusive book: How Katrina changed all of us

Critics saw it not as a sign of his concern but as a demonstration of his distance, and Katrina became a kind of political shorthand. Pundits would debate when and whether the presidents who followed were having "their Katrina moment" – that is, a misstep that risked their reputation and their support.

'The hand of God had wiped away the coast'

Twenty years later, Haley Barbour, then the Republican governor of Mississippi, remembers Katrina and its devastation. "It looked like the hand of God had wiped away the coast," he said in an interview. The storm and floods killed 238 residents of his state and leaving billions of dollars in damages − though he also remembers the outpouring of help from across the country as the state rebuilt.

Twenty years later, Ruffin remembers Katrina, too, and wonders how it reshaped him, and the country. "I am still an optimist, but I wonder if I would've been more of an optimist had that not happened," he said. "There have been many moments in American history that I think have changed our attitude toward ourselves."

For him and others, Katrina still stands as one of those moments.

Twenty years later.

This article originally appeared on USA TODAY: America remembers Hurricane Katrina. But how about its lessons?

Reporting by Susan Page, USA TODAY / USA TODAY

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