Fact-checking Trump’s lies is essential. It’s also increasingly fruitless.

So, so much was simply wrong. Claims about the border wall, about drug prices, about unemployment, about his response to the pandemic, about rival Joe Biden’s supposed desire to defund the police (which Biden has said he opposes).

Dale is a national treasure, imported last year from the Toronto Star, where he won accolades for bravely tackling the Sisyphean task of fact-checking Trump. My skilled colleagues of The Washington Post Fact-Checker team, who recently published a whole book on the president’s lies, have similarly done their best to hold back the tide of Trumpian falsehoods.

Dozens of organizations, from Snopes.com to FactCheck.org and many others, are kept busy chasing political lies, so many of which come from the current White House. But here’s the rub. More than a decade after the innovative Florida-based fact-checking organization Politifact.org won a Pulitzer Prize, fact-checking may make less of a difference than ever.

More and more, fact-checkers seem to be trying to bail out an ancient, rusty and sinking freighter with the energetic use of measuring cups and thimbles.

“My biggest takeaway of the last four years is probably realizing the extent to which big chunks of America are living in a different universe of news/facts with basically no shared reality,” was how Charlie Warzel, who writes about the information wars for the New York Times put it last week.

I happened to be sitting in the WAMU studio in late 2016 when Scottie Nell Hughes — then a frequent surrogate for President-elect Donald Trump and a paid commentator for CNN during the 2016 campaign — said something startling, live on the Diane Rehm radio show: “There’s no such thing, unfortunately, anymore, (as) facts.”

Rehm had pressed her about Trump’s false assertion that he, not Hillary Clinton, would have won the popular vote if millions of immigrants had not voted illegally. That was a claim he seemingly had heard on Infowars — the conspiracy-theory-crazed site run by Alex Jones, who at one time claimed that the 2012 massacre of 20 children and six staff members at an Connecticut elementary school was a government-sponsored hoax.

Hughes gave not an inch of ground: Trump’s false claims, she insisted, “amongst a certain crowd . . . a large part of the population, are truth.”

Belief, therefore, takes the place of fact.

The situation has only become worse since then. And as scholars have observed, calling out falsehoods forcefully may actually cause people to hold tighter to their beliefs.

That’s the “backfire effect” that academics Brendan Nyhan and Jason Reifler wrote about in their study “When Corrections Fail” about the persistence of political misperceptions: “Direct factual contradictions can actually strengthen ideologically grounded factual beliefs.”

Not knowing what media sources to believe — and the growing mistrust in the press among many segments of the public — has added to the problem of politicians who lie.

Last week, I was asked to settle a family dispute about the believability of a news report that had been circulating on a group text-message chain.

One family member (I’m being vague since I hope to continue to be invited to Thanksgiving dinner) was outraged by the supposed revelations in a Newsweek article whose headline read “Brand New Mail Sorting Machine Thrown Out at USPS Center, Leaving Workers Sorting by Hand.”

Another family member had serious doubts about whether this was true. He dismissed it as “hearsay.”

And a third asked me to take a look: Would I have published the article?

It didn’t take me long to decide it wasn’t credible or publication-worthy. Newsweek, despite its legacy name, is suspect from the start these days. The article’s sourcing was thin. And a hyperlink, its main piece of evidence, led me to a local news site that already corrected the main element of its story. (Days later, Newsweek still hadn’t updated its story.)

These family members care about the facts, and were engaged enough to be curious about whether a report is accurate. And while it may have suited their politics better if it were true, they were open to hearing that it wasn’t.

But most people don’t have the time or energy to do research projects on the news they are reading, or the claims they are hearing from the White House, or the conspiracy theories that flood their Facebook feeds.

Most people no longer share with their fellow citizens the trust in news organizations — or in political actors — that would give them confidence in a shared basis of reality. And worst of all, the flow of disinformation on social media is both vile and unstoppable.

In this world, challenging official lies and seeking truth remains necessary, even essential. The yeoman’s work of Daniel Dale, and others like him, remains appreciated.

But I’m with Warzel on this: As Americans, we’re in trouble when it comes to a common ground of reality on which to stand.

And no amount of fact-checking is going to solve that overwhelming problem.

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