President Trump attends a rally in Moon Township, Pa., on March 10. (Keith Srakocic/AP)
Media columnist

Even before the 2016 presidential election, CNN’s top honcho admitted that his network had given Donald Trump too much free exposure in the Republican primary.

“If we made any mistake last year, it’s that we probably did put on too many of his campaign rallies in those early months and let them run,” Jeff Zucker said at a talk at the Harvard Kennedy School in October 2016.

But it made for great TV, he explained: “Listen, because you never knew what he would say, there was an attraction to put those on air.”

Translation: It’s all about the ratings.

Don’t look now, but it’s happening again. And it’s still the wrong thing to do.

Last weekend, some cable networks carried Trump’s rally in Pennsylvania live for more than an hour, as the reality-star president once again uttered outrages and kept the focus squarely on himself — even while purportedly boosting Republican congressional candidate Rick Saccone.

“To broadcast a 75-minute campaign rally, uninterrupted, demonstrates cable managers’ deficit of imagination, resources, or both,” Bill Grueskin, a professor at Columbia University’s Graduate School of Journalism, told me. “There’s just too much going on in this country and in the world to justify it.”

And Norman Ornstein, resident scholar at the American Enterprise Institute, chastised CNN on Twitter: “Carrying Trump water even as he abuses you.” (Trump has, of course, mocked and disparaged CNN at every turn, including urging crowds to chant “CNN sucks!”)

The over-the-top coverage, though, had plenty of defenders.

Chris Cillizza of CNN, formerly of The Washington Post, put in simple terms what many others were saying: “Donald Trump is the president of the United States. When he speaks, we cover it. As we should.”

And liberal columnist Joan Walsh agreed: Don’t air the empty podium as CNN did during the primary campaign, she wrote, “but when he starts talking hate and racism, like tonight, it’s news.”

And as my colleague Philip Bump pointed out, this is not a first. President Barack Obama’s 30-minute speech at a rally for Senate candidate Martha Coakley of Massachusetts in 2010, for example, was carried live on some networks.

But for Trump, free TV time is not only pure political gold but also an opportunity to insult, to abuse and to spread falsehoods.

On Saturday, he worked an appalling slam of the moderator of NBC’s “Meet the Press” into the rally.

“Sleepy eyes Chuck Todd, he’s a sleeping son of a bitch,” said the president of the United States. Trump also called for executing drug dealers and falsely claimed that 52 percent of women voted for him — it was actually 52 percent of white women, according to exit polls.

There’s no question that Trump’s newsworthy statements at a campaign rally should be covered in some form. That’s a journalistic imperative — although he often reverses his public statements with little explanation, as he did recently in first supporting gun-control measures and then acceding to the National Rifle Association’s wishes by backing down.

But covering him doesn’t have to mean broadcasting him live for more than an hour. That’s nothing but an unearned gift to his 2020 reelection campaign — the planned slogan of which (“Keep America Great!”) he talked about at the rally.

Another TV executive, Les Moonves of CBS, infamously said during the presidential campaign that, because of swelling ad dollars, Trump’s ascendancy “may not be good for America, but it’s damn good for CBS.”

That profits-above-all line of thinking clearly is alive and well.

Yes, the president’s statements at a campaign rally, or elsewhere, may be newsworthy. They should be reported on, fact-checked and put in context — not aired in their self-serving entirety as though he were a dictator with control over the state airwaves.

We’ve already seen that episode and it didn’t end well.

An antiwar protest song wondered, “When will they ever learn?” The answer, apparently, is “never.”

For more by Margaret Sullivan visit wapo.st/sullivan