These days, not a day passes without an eruption of hostility among high-ranking members of the  Trump administration. Whether it’s President Trump lashing out at Attorney General Jeff Sessions or Communications Director Anthony Scaramucci blaming Chief of Staff Reince Priebus for media leaks, the intra-White-House warfare seems relentless.

But internecine conflict has always been part of presidential administrations. During the Reagan years, Nancy Reagan and White House Chief of Staff Donald Regan loathed each other, and the first lady helped engineer his ouster in 1987. During the presidency of George W. Bush, Secretary of State Colin L. Powell was famously at odds with Vice President Richard B. Cheney and Defense Secretary Donald H. Rumsfeld.

But perhaps the most epic White House feud was the smackdown between Vice President Lyndon B. Johnson and Attorney General Robert F. Kennedy. The two men’s hatred of each other began as soon as Johnson was selected as John F. Kennedy’s running mate in 1960, and never really ended — not even when Bobby was buried at Arlington National Cemetery in 1968.

Unlike today’s broadsides that instantly travel from the mouths or fingers of the attackers straight to everyone’s handheld devices, LBJ and RFK sniped at one another privately, with the most quotable insults appearing in books decades after the men wielded power.

You think Trump was nasty calling Sessions “beleaguered” or saying that he’d taken a “VERY weak position” on the alleged crimes of Hillary Clinton? You think Scaramucci sounded furious when he likened his relationship with Priebus to Cain and Abel, which ended in murder? Or told New Yorker writer Ryan Lizza that “Reince is a f— paranoid schizophrenic, a paranoiac.”

LBJ and Bobby despised each other so much that an entire book — 576 pages — was written about their enmity. It’s called, quite naturally, “Mutual Contempt: Lyndon Johnson, Robert Kennedy, and the Feud that Defined a Decade.” It was written in 1997 by Washington writer Jeff Shesol and received glowing reviews in The Washington Post and the New York Times.

This is how the book begins:

“‘Lyndon Johnson and Robert Kennedy loathed each other. ‘This man, said of Johnson, ‘is mean, bitter, vicious — an animal in many ways.’ Johnson considered Kennedy a ‘grandstanding little runt.’ Their mutual contempt was so acute, their bitterness so intense and abiding, they could scarcely speak in each other’s presence.”

Sometimes, the men shouted at each other, and when they were apart, they often “sulked and brooded” about the other, Shesol wrote.

The animosity began in earnest in 1960, when LBJ, then the Senate Democratic Majority Leader, and Jack Kennedy were vying for the Democratic presidential nomination. Initially reluctant to spar, LBJ ultimately resorted to attacks two months before the Democratic convention. Johnson’s men accused the Kennedys of buying votes in Oregon and West Virginia. Johnson attacked Kennedy’s Catholic faith and told a reporter for The Chicago Daily News that Jack was a “little scrawny fellow with rickets.”

“‘Have you ever seen his ankles? They’re about so round,’ ” Johnson said, tracing a petite circle in the air with his finger,” according to Shesol’s book.

LBJ’s constant insults infuriated Bobby, who already viewed his brother’s opponent as a prevaricating power broker.

“Bobby, more than Jack, took this stuff personally and reacted with rage,” Shesol said in an interview. “And he hated politicians who get in your face and lie. He hated politicians who felt like politicians, and Johnson was the perfect distillation of someone who lived and breathed politics of the old style.”

During the 1960 convention, Jack won the presidential nomination. But when he selected Johnson as his running mate, he and others in his camp immediately questioned the choice. It fell to Bobby to persuade LBJ, ever so diplomatically, to decline the offer.

He made three visits to Johnson’s hotel suite during the convention. LBJ hated him from the start.

“Whatever it is, I don’t want to see him,” Johnson told his advisers, according to “Mutual Contempt.”

“Johnson liked JFK but loathed Bobby and was convinced Bobby had done this of his own accord,” Shesol said in an interview with The Washington Post.

When JFK and Johnson were sworn into office in January 1961, Bobby was appointed to be attorney general. Relations did not improve. The Kennedy brothers, Shesol said, worked to sideline Johnson as much as they could. Given Johnson’s appetite for power, he chafed mightily at his marginalization.

“Johnson was an extremely powerful majority leader, and he expected to take on a major role as vice president. He was not looking quietly to go into the second seat,” Shesol told the Post. “But it was Robert Kennedy who emerged as the number two man in Washington. And Johnson raged at his impotence — and blamed it all on Bobby.”

And yet, neither of them publicly disparaged each other. Yes, Bobby whispered critically about Johnson, some of which was leaked to reporters, Shesol said, but always off the record.

“Johnson grumbled to his staff about Bobby, but he never said a word to the press,” Shesol said. Only later did anecdotes about their enmity leak out to historians — an encounter, for example, during which Bobby interrupted his brother in the Oval Office while he was meeting with LBJ, and never acknowledged him.

Perhaps the nadir occurred on Nov. 22, 1963. Bobby was sitting poolside at his family’s home in McLean, Va. He’d just gotten word from FBI Director J. Edgar Hoover that Jack had been assassinated in Dallas, and now Johnson was calling. The vice president had pressing questions for the nation’s chief legal adviser, who happened to be the dead president’s brother.

Johnson wanted to know: Could he be sworn in right away as president? Did Bobby have objections? Who could swear him in? And when? And how?

RFK was shocked into momentary silence.

Bobby stayed on as LBJ’s attorney general through 1964. Johnson needed him for his own legitimacy, and RFK wanted to play a role in the enactment of the landmark Civil Rights Act of 1964, barring discrimination based on race, color, religion, sex or national origin.

In 1964, Bobby was elected to the Senate from New York. The feud between the two men became more public, Shesol said. The media became obsessed with the rivalry, as Bobby lobbied for a pause in the bombings in Vietnam during the war. In 1968, RFK declared he couldn’t support Johnson for reelection, and he decided to challenge him for the nomination. Johnson bowed out of the race, but he never forgave Bobby.

Even after Kennedy was assassinated on June 5, 1968, Johnson couldn’t resist a fight with his foe. Within hours of the news, Johnson called up his defense secretary, demanding to know whether Bobby had the legal right to be buried at Arlington National Cemetery, according to “Mutual Contempt.” Johnson was told it was up to him. He finally relented, figuring he would face political suicide if he stopped it.

After Bobby’s death and burial in a temporary spot, the Kennedys asked that the federal government help pay for a permanent graveside for Bobby next to his brother’s. They wanted the government to maintain the foliage and landscape, basically.

But LBJ delayed approving the plan. It wasn’t until January 1969, during his final days in office, when he instructed the Bureau of the Budget to add $431,000 to the president’s 1970 contingency fund. He was leaving the ultimate decision to his successor — Richard Nixon.

“And in a final, petty display of bitterness undiminished by tragedy,” Shesol wrote, “LBJ omitted specific mention of the Kennedy grave from his budget.”

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