WASHINGTON — Forty years after Watergate, a central question lingers: Did President Nixon's misdeeds and downfall strip the nation of its innocence or affirm the resilience of the American system?

In one vision, Watergate turned Americans into cynical people, mistrustful of government, ready to believe the worst of their leaders. Forty years after the botched burglary, the squalor of Nixon's presidency remains visible in our paralyzed, polarized politics, our alienation, our insistent disunity.

Alternatively, Watergate shines as proof the system works, that law and the Constitution prevail over the excesses of craven politicians. Details of the scandal, which resulted in the only resignation of a president in U.S. history, may fade with time, but Watergate lives on in the idealism of those who hold government to account — through grass-roots movements such as the tea party and Occupy Wall Street, investigative reporting, and public and private watchdog groups.

The principal figures in the Nixon presidency and the two-year drive to reveal its misdeeds are mostly elderly men now, and the scandal that riveted the nation barely is mentioned in most high-school history courses.

But in politics, popular culture, the news media and the perception of the United States at home and abroad, Watergate was a watershed, the beginning of an era of inspection, the end of a more deferential culture, a turning point with as powerful an impact as the Vietnam War or the civil-rights movement.

"Our long national nightmare is over," the new president, Gerald Ford, said in his first address after Nixon resigned in August 1974. "Our Constitution works; our great Republic is a government of laws and not of men. Here the people rule."

That notion of Watergate governed for many years; in 1974, Americans elected to Congress a huge class of idealists bent on reforming the nation's institutions and wresting power from the few.

Reporters became unlikely heroes, portrayed by Hollywood and best-selling books as so many Davids taking on dubious Goliaths of politics and business. Whistleblowers — once derided as disloyal snitches — became a protected class, celebrated in pop culture and defended by new laws.

Scandal's nuances fade

As the years slip by, the Watergate story — the tale of a criminal conspiracy to cover up misdeeds by a president and his top advisers — drifts toward myth, losing some of its nuance. Fact and fiction blur. Hollywood's rendition takes up more bandwidth than the original investigative journalism.

The 1976 movie version of "All the President's Men" — the film about Washington Post reporters Bob Woodward and Carl Bernstein that inspired a generation of journalism students — made it into the American Film Institute's list of 100 best movies and remains an oft-rented classic.

Only a couple of decades after the scandal, an academic study on Americans' collective memory concluded "the only vivid personal memory of Watergate was the feature film 'All the President's Men.' "

Yet in subjects as disparate as campaign financing, media responsibility and corporate ethics, Watergate is still regularly summoned as an explanation for today's troubles.

"Watergate was the onset of the change in relationships between Republicans and Democrats," said Tom Railsback, 80, a Republican congressman from Illinois from 1967 to 1983 and a member of the House Judiciary Committee that voted to impeach Nixon.

"It made the American people very cynical about government and created a real mistrust between the parties. Before Watergate, Republicans and Democrats traveled together, our families were friends, and we would seldom report out legislation that didn't have support from members in both parties."

Balderdash, says Elizabeth Holtzman, a New York Democrat who served on Judiciary with Railsback and was in the House from 1973 to 1981. "I know it sounds corny," she said, "but the members of the Judiciary Committee put country above party and above their personal re-election chances to act together against criminal acts by the president. It's ludicrous to argue that the ability of Republicans and Democrats to act together then created a schism between the parties."

Watergate, according to Holtzman, 70, ultimately was a triumph for voters, who realized their error in re-electing Nixon in a landslide victory in 1972, and just a year later supported Congress, the courts and the press in "an affirmation of our system of checks and balances, working together in a historic high point in our relationship with our government."

Watergate, like so many signal moments in history, morphs over time, its meaning evolving with shifting ideologies, emerging technologies and new waves of scandal.

Remnant in language

The primacy of pop culture has nudged Watergate's meaning in a less serious direction, historians say, even in how the scandal's name is used. The word sleuths of the Oxford English Dictionary found other scandals adopting the "-gate" suffix only two months after the burglary, setting a pattern that has lasted from Billygate, the 1980 brouhaha over the behavior of President Carter's untamed brother, to Climategate, the 2009 controversy over whether British climate scientists had cooked the books in a study on global warming.

Now "-gate" has become an ironic touch, a way to indicate a controversy is not exactly weighty.

Watergate remains a serious academic topic; many state curricula require social-studies teachers to present the scandal as a lesson on the division of powers among the three branches of government. But what the curricula say isn't always what happens in class.

"On a practical level, Watergate has really receded as a topic that people teach," said Steve Armstrong, vice president of the National Council for the Social Studies and supervisor of social studies for the West Hartford, Conn., school system. "I'm 59, so Watergate is huge to me, but anything that old is ancient history for young people. For many young teachers, Watergate is just one event among many of this nature."

Young teachers also present students with a more charitable view of Nixon, he says, giving Nixon's overtures to communist China and the Soviet Union at least equal time against Watergate.

President Clinton's sex scandal involving Monica Lewinsky gets more classroom time than Nixon. "They go with the stuff they know they can get the kids interested in," Armstrong said. "The attitude is, 'Yeah, yeah, Nixon got caught, but what president doesn't do something like that?' "

D.C. cultural shift

Whether the news media merely reflected that dark view of politicians or encouraged its spread, Watergate dramatically altered the relationship between those in power and those who report on them.

As the investigation into impeaching Nixon gathered steam in 1973, Railsback, the Illinois congressman, headed home for Christmas recess. He was startled to find he was not alone. Everywhere he went — his daughter's elementary school, a high-school basketball game — there were his new shadows, Sam Donaldson of ABC News, and Ike Pappas of CBS.

"It was a startling new experience," Railsback said. "Members of the House were not subject to much media scrutiny back then. All of a sudden, we were center stage."

Four decades later, Washington, D.C.'s image as a place where voters send representatives to work in relative obscurity, devising federal policy, is shattered. Some politicians say the paralysis that infects the capital stems from forces unleashed by the scandal — interest groups intent on countering government power, as well as a media that discovered reader interest and profit in more aggressive coverage.

"The culture of Washington changed in response to Watergate, with a huge shift in journalism toward questioning authority," said David Greenberg, a Rutgers University historian, a former research assistant to Woodward and author of "Nixon's Shadow: The History of an Image."

"That led to the investigative work of the new muckrakers, but also to a gotcha journalism, with a lot of noise and heat over unimportant stories, and both forms changed the political culture."

Almost immediately after Watergate, young people, inspired by the central role that Woodward and Bernstein played in unraveling the Watergate conspiracy, flocked to journalism schools.

And despite recent waves of cost-cutting in print and broadcast news organizations, enrollment in undergraduate journalism programs nationwide has jumped by 35 percent in the past decade. Watergate remains a touchstone for budding journalists eager to demonstrate that right can tame might.

"It's definitely still part of the lore and a serious driving force," said Mark Horvit, executive director of Investigative Reporters and Editors, a nonprofit created to support the expensive work of keeping government accountable.

Big question lingers

Even now, the flow of books and papers about Watergate continues unabated, as historians, partisans and novelists try to make sense of what happened and to answer a key question: Why did the president and his staff, coasting toward easy re-election, commence a campaign of dirty tricks?

If Watergate has been diminished by time, that's just how history works, often becoming kinder to bad guys as years go by. In Thomas Mallon's novel "Watergate," Nixon emerges as a more nuanced figure than the easily spoofed figure of most early books about the era.

"The Nixon in my book is still guilty of many things," said Mallon, who teaches creative writing at George Washington University and who was in college during Watergate. "But he's in over his head. He's confused."

With the anniversary of the break-in Sunday, Woodward, whose reporting has focused mainly on presidential power and warfare in recent years, has been listening again to the Nixon tapes. "Revisionism is inevitable," he said, "and it should be part of the process. However, every season, there's a new batch of Nixon tapes that once again establishes his criminality, his regular abuse of power and the nature of his personality."

The 40th anniversary is likely the last important one in Watergate's history, Mallon says. By the 50th, fewer important figures from the scandal will be around to debate the meaning of the events or to recall with vivid detail the sense in 1973 that the country was in danger of collapsing under the scandal.

Mallon remembers that burden of living every day with a slow-moving but devastating crisis. And he recalls the invigorating end to the scandal: "People talk of Watergate as a moment when America lost its innocence, and there's probably something to that," he said. "But the entire thing happened without a soldier in the street, without a gun being fired. It showed the sophistication of American law and life."