President Nixon, left, walks with his presidential press secretary, Ron Ziegler. (AP)

This story has been updated to reflect White House press secretary Sean Spicer resigning on Friday.

In late August 1973, as the Watergate scandal ate away at President Richard Nixon’s psyche and presidency, CBS News correspondent Dan Rather filed an astonishing report on the evening news.

“What you are about to see,” Rather said, “is a rare glimpse in public of presidential irritation.”

And there it was on tape: The president of the United States grabbing press secretary Ron Ziegler by the shoulders and shoving him away.

Ziegler, by now, was a familiar and reviled figure, the man who called the Watergate scandal a simple “third-rate burglary.” Nixon, by now, was facing a special prosecutor. For the first time in months, Nixon ventured out of Washington to give a speech — to a veterans group in New Orleans.

There have been many comparisons between Nixon and President Trump of late, as the nation’s 45th president faces a series of scandals, including a special counsel investigation into whether the Trump campaign colluded with Russia. But whatever Sean Spicer endured before resigning as press secretary on Friday — a significant blow to Melissa McCarthy — it seems unlikely to be comparable to Nixon’s treatment of Ziegler that summer day in 1973.

“Even by Nixon’s usual standards,” wrote historian David Greenberg, “his behavior in New Orleans was bizarre.”

[Trump’s team studying pardon law — including for the president himself]

Nixon was walking toward the convention hall, toward his first friendly audience in months.

“He wanted nothing in his way, in front or in back, before he got at the crowd inside,” The Washington Post’s magazine later reported in a profile of Ziegler. “But breathing on him from behind was Ziegler and the clump of TV cameras, mics and newsmen that inevitably followed.”

Nixon’s famous temper was activated.

He stuck his finger in Ziegler’s chest, turned him around, and then shoved him in the back hard with both hands, saying “I don’t want any press with me and you take care of it.”

Rather saw it with his own eyes. His cameraman got it on tape. (You can watch here.) When Rather rushed to ask a president’s aide about the incident, he was told nothing happened. Rather seethed, recounting the conversation with the aide in New York magazine a year later:

“Why did the president push Ron Ziegler?”
“He didn’t push him.”
“I’m telling you, we’ve got film of him pushing him.”
“Well, it just didn’t happen.”

Rather viewed the tape. He called White House officials and told them he was literally watching the president of the United of States shove his press secretary. Rather was informed that he misinterpreted what his camera recorded. He ended his segment that evening saying, “The president’s aides deny he is nervous or testy anything.”

But Nixon wasn’t denying what happened, at least not to Ziegler.

“Afterward, on the plane going home, he came up to me and put his hand on my shoulder, in front of the whole staff, and apologized,” Ziegler told The Post in 1981.

There had been, he said, some sort of assassination threat.

“And more Watergate stuff was starting to come out,” he added.

Nixon didn’t want to hurt him.

“It was not a shove of anger,” Ziegler says. “It was a shove of frustration.”

For Nixon, the event fueled concern about his mental health, both from his staff and the reporters covering his collapse.

In Rolling Stone, Hunter S. Thompson wrote: “Another good bet in Washington — running at odds between 2 and 3 to 1, these days, is that Nixon will crack both physically and mentally under all this pressure. ….This is not so wild a vision as it might sound — not even in the context of my own known taste for fantasy and savage bias in politics.”

The pressure, Thompson wrote, must be crippling.

“I have to admit that I feel a touch of irrational sympathy for the old bastard,” he wrote.

Ziegler, who died in 2003, forgave his boss.

“I understood the situation fully,” he told The Post.

But he couldn’t deny what was plainly apparent, even if Nixon’s administration tried to with Rather.

“Obviously,” Ziegler said, “I was humiliated.”

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