Jim Acosta, CNN’s chief White House correspondent, knows the terrible things people say about him on social media.

No one person could keep track of all the comments, and Acosta turned off his Twitter alerts several years ago — partly because of the volume of messages, but also because President Donald Trump’s supporters started harassing him and making death threats.

Cesar Sayoc, the man who pleaded guilty to sending pipe bombs to CNN and top Democrats, also posted nearly a dozen messages about Acosta, including one showing a decapitated goat.

This, in the Trump era, comes with the job of asking challenging questions of the president.

“One of the things that has been an education for me is the wild west of social media,” Acosta told me recently by phone from Washington. “It’s a new frontier for harassing and bullying journalists.”

I invited Acosta to speak at the Pittsburgh Playhouse on Feb. 6 as part of the Media Innovators Speaker Series, but not because of his politics or mine. Instead, it was his journalistic approach of asking challenging questions — in his words, of being an “equal opportunity pain in the butt” — to anyone in power.

Is he tough on Trump? Yes, that’s who runs the White House. But before that, Acosta asked difficult questions of President Barack Obama and Cuba’s President Raúl Castro, and many others.

Also, unlike many of his inside-the-Beltway contemporaries, Acosta cut his teeth in local television, working at stations in Knoxville, Dallas and Chicago before going back to his hometown of Washington, D.C.

Having worked in both Washington and in local news, I know that you have to keep your elbows out when dealing with small-town officials as much as you do with Congressional lawmakers and White House executives.

I hoped that Pittsburghers would get to see a human side of Acosta by meeting him in person, and hearing about how he came up through the business and why he feels so strongly about journalistic traditions and responsibilities.

I did not, however, expect so many Pittsburghers to react negatively to Acosta’s appearance. The Pittsburgh Playhouse’s Facebook page, where we promoted the event, carries nearly 200 comments from people saying mostly disparaging things about Acosta and his work:

  • One Pittsburgh man who says he works for a candy company and looks like a tuxedo-wearing gentleman had this to say: “Jim Acosta is a self-serving narcissist … He acts out to gain self-indulgent attention while trying to push his left-leaning agenda.”
  • A retired teacher from Monaca who posts darling photos with her cute grandchildren wrote: “I wouldn’t walk across the street to see [Acosta]. What a terrible choice for a speaker!”
  • A Greensburg woman who raised money on her birthday to help kids with cancer said: “[Acosta] is a self-serving idiot that cares nothing about reporting the truth. Fair journalism is a thing of the past!”

My point is that these all seem like decent, hard-working people based on their other posts about their families and their pets. They’re all people we recognize and know. They are our neighbors and friends.

But when it comes to Acosta and CNN and asking honest questions of the president, these people think nothing of going on social media to say mean-spirited things.

Acosta, of course, takes in a broader scope for this behavior because he encounters it all across America. He has bodyguards who travel with him to campaign rallies because of the hecklers and because of the potential for others like Sayoc, who might try to do actual harm to him.

Acosta’s New York Times bestselling book, “The Enemy of the People,” takes its title from the president’s words, who has called out journalists and news stations as if he’s a Third World despot or a small-town mayor who cannot handle legitimate scrutiny from the Fourth Estate.

“It’s a deeply destructive force in our politics right now … ,” Acosta told me. “[Trump] has done this; he has put a bull’s eye on the backs of reporters. And I think what has happened is that some, not all, of Trump’s supporters have absorbed this rhetoric and directed it back at us in ways that make us feel endangered and threatened.”

Reporters who question this administration and hold power accountable get labeled as troublemakers.

We saw it again recently when Secretary of State Mike Pompeo berated an NPR journalist for asking about Ukraine and why he had not done more to protect the United States’ ambassador there. That’s a legitimate question, but Pompeo responded with a tirade and by blocking another NPR correspondent from the State Department’s next overseas trip. Trump applauded him.

Politicians rarely like it when we ask questions that challenge their authority. I certainly have had plenty of elected officials — governors, lawmakers, mayors, council members — criticize me for asking difficult questions. Sometimes they lashed out, and other times they simply refused to answer.

More than once, that frustration turned personal.

A government employee joked about running me over with his car after I worked on an investigative project about how his office had been managing taxpayer money.

Mayor Tom Murphy used me as a foil in a Hill District speech about how suburbanites come into the city to work when he wanted to win approval for a commuter tax.

It happens. At the local level, politicians play to a smaller audience.

On a national stage, the president uses aggressively harsh words to call out journalists on television, on social media and at his rallies. He does this with little apparent regard for their safety. And his supporters run to the scent.

“My concern is that you can have a situation that is so volatile where you have a reporter who is seriously hurt or killed,” Acosta said. “We can’t have a situation like that in this country. At the moment that that happens, we cease being the United State of America that you and I grew up in. You can’t have journalists getting hurt and beat up and that sort of thing because one particular politician’s supporters don’t like the coverage.”