The election of Donald J. Trump has led to considerable soul searching in the news business, as journalists confront the role we played in his triumph. Much has been written about the billions of dollars of free media coverage Trump received, journalists’ lapses in challenging his outrageous falsehoods, and our clumsy grappling with how to treat his unconventional candidacy.

But the news coverage that helped Trump the most wasn’t about the campaign. It began long before it — decades before his candidacy, in fact. Trump was the beneficiary of a belief — near universal in American journalism — that “serious news” can essentially be defined as “what’s going wrong.”

A lot has gone wrong across the country, especially for Trump’s core supporters, the white working class — who have suffered serious economic and social dislocation. Many feel powerless and resent elites and journalists, whom they find arrogant and condescending. Trump gave voice to their grievances and placed their personal struggles within a larger narrative of national decline — a decline that, he said, was so sharp and frightening that revolutionary change was needed, and only he knew how to deliver it.

To make his case, Trump recounted a near-daily vision of a government hopelessly broken and corrupt, cities that had become “hellholes,” military leaders who resembled the Keystone Kops, immigrants flooding into the country stealing jobs — when they’re not raping and killing. In America’s inner cities, he said, you saw: “Poverty. Rejection. Horrible education. No housing, no homes, no ownership. Crime at levels that nobody has seen.”

Crime is, in fact, at unusual levels, but it’s unusually low levels — close to the lowest rate in 45 years. Immigrants are less likely to commit crimes than their native-born peers and twice as likely to start businesses. In many parts of the country, the public institutions that people count on every day like schools and hospitals have improved, thanks to a wide range of reforms and initiatives. In the past few years, there have also been steady gains in employment and wages, although work is less predictable than in the past and many Americas remain insecure and discouraged.

The state of the union is mixed. So why did so many people accept Trump’s dark vision? One answer is that it fits with what they feel from the news. In this case, it doesn’t matter if it’s left- or right-wing news. Where can you count on finding stories every day about violence, social dysfunction and government incompetence and scandal? When is the last time you read a news story about government competence? What are the images from the news that readily come to mind about African-Americans, Latinos, Muslims or immigrants? Do you picture people with aspirations who are studying, making contributions, building businesses? Or do you picture lawlessness, drug use, dysfunction?

For decades, journalism’s steady focus on problems and seemingly incurable pathologies was preparing the soil that allowed Trump’s seeds of discontent and despair to take root. Today, this problem is magnified by the fragmentation of news sources and a proliferation of fake news. One consequence is that many Americans today have difficulty imagining, valuing or even believing in the promise of incremental system change, which leads to a greater appetite for revolutionary, smash-the-machine change, as we have seen in this election. A survey from the Pew Research Center published last week found that 53 percent of Trump supporters, but only 16 percent of Clinton supporters, felt it was more effective to try “New approaches that may solve problems quickly, but also risk making things worse.”

The erosion of belief has been gradual. It didn’t begin with the internet or cable TV, and it is not entirely because of the new enthusiasm for getting news from social media or late-night comedians. It can, ironically, be traced instead to the years of the Vietnam War, Watergate, C.I.A. surveillance of Americans and other profoundly disillusioning experiences in the 1960s and 1970s, when reporters were doing what the originators of the First Amendment had in mind — checking the power of public officials by holding them accountable.

That was a public service, and it ended a more permissive era when a more timid brand of journalism glorified leaders, knowingly looking away from their personal and professional lapses. Unfortunately, the pendulum swing led to a new problem: hypercynicism, with virtually everything about America’s leaders, power brokers and civic actors, including their private lives, fair game for scrutiny. Speaking truth to power now meant taking down all icons, exposing all pretension and looking for self-interest and “spin” everywhere.

The effect on the social fabric has been corrosive. Since the early 1970s, surveys conducted annually have revealed that trust and confidence in virtually all American institutions — government, corporations, banks, medicine, education, organized religion and, yes, the press — have been declining steadily.

Even worse, over the past four and a half decades, Americans have become significantly less trusting of one another as well. From 1972 to 2012, the percentage of respondents to the General Social Survey who said that most people can be trusted dropped to 32 percent from 46 percent. In parts of the Midwest, the drop was particularly dramatic — from about 60 percent to the mid-30s.

Disillusionment and cynicism have become natural byproducts of everyday journalism. We’re not talking about politically tainted news, or the “If it bleeds, it leads” reflexes of local TV coverage, which provide nightly reinforcement of the threat of violence from strangers — even as that threat is negligible for the vast majority of people.

We’re talking about a problem at the very core of journalism: the unstated theory of change that might be summed up as: “Society will get better when we show where it is going wrong.” We are presenting what’s wrong with the world as if that’s all there is.

As a result, what audiences see beyond their direct experience is a world of unchecked pathology, and it makes it all too easy to fear and demonize others. It shapes people’s behaviors and choice of leaders. During the election, citizens had considerable information about the candidates, and they knew about their own lives and problems. But they were easily bamboozled about the extent and nature of problems in the country and the world.

We’re actually pretty bullish on our own neighborhoods and cities. That may be why Americans who wanted to drain the Washington swamp re-elected congressional incumbents almost across the board. It’s when we have no firsthand information and must rely on the news that the world gets scary. And in 2015, six of the Associated Press’s Top 10 news stories were about gruesome acts of mass violence.

What happens when the story is not about carnage but about courage? When Ebola was rampant, headlines promising global catastrophe dominated the news. The thousands of deaths in Liberia, Guinea and Sierra Leone incited global fear. But Mali contained Ebola with only eight cases. Nigeria contained it with 19 cases. Senegal stopped the virus after a single case. Did journalists deliver resounding headlines about how these countries achieved these successes? Did they follow up with stories of government competence after harping on government incompetence? Of course not. There is now an Ebola vaccine, which was developed with remarkable speed — in time, in fact, to end the epidemic. How many journalists focused on that? Billions of people were terrified by Ebola. Do even a few thousand know about the vaccine?

Every major problem presents opportunities for reporters to show how people are responding. Whether an effort fails, is marginally successful or works well, it provides information crucial to democracy. It shows that people care. It helps new ideas circulate. It shows that incremental system change is possible. It shows that beyond your direct experience, there are other communities where people who look different from you are also trying to build a better society. This nurtures the respect that makes society work.

Journalism has a language with which to describe threats and failures, but it is tongue tied when it comes to letting society know when there’s a win. Part of this is simple sensationalism. But perhaps more important is that journalists have become afraid to cover remedies, lest we seem gullible (which, for a journalist, is the greatest sin). We are comfortable, however, covering failure, and adding to the narrative of decline.

This distortion of reality takes a toll. We know from psychological research that a steady diet of news about violence, corruption and incompetence leads to increased fear, learned helplessness, hopelessness, cynicism, depression, isolation, hostility, contempt and anxiety. The journalist Walter Lippmann wrote: “The way in which the world is imagined determines at any particular moment what men will do.”

In the wake of Trump’s election, we need to ask if today’s approach to news is tenable for a democracy whose survival depends on the belief and agency of its citizens.