President Obama Welcomes Donald Trump as Newest Member of The Presidents Club

The White House meeting of President Barack Obama and President-Elect Donald Trump follows a tradition of animosity giving way to assistance that dates back to 1952. No matter how personally or politically hostile an outgoing and incoming president may be, once voters have selected a new member of The President’s Club, a different dynamic takes over. Only those who have held the job can understand what it does to you, or the help that you need to succeed at it. And so upon the election of a new president, the sitting president takes the opportunity to pull back the curtain, and give his successor a glimpse of the challenge that lies ahead.

The tradition began with Harry Truman. After an utterly brutal and bruising campaign, Truman invited the newly elected Dwight Eisenhower to the White House; then as now, the two men could not stand one another. Truman and Ike had been friends and allies in the early years of Truman’s presidency, working together in World War II’s aftermath to erect the post-war security structure. But that had changed by 1952 when Eisenhower hung up his uniform and aimed for the White House, another political outsider whose party affiliation was in doubt until he entered the New Hampshire primary and had to affirm that he was, in fact, a Republican. Eisenhower’s attacks on the Truman administration during that campaign, and his failure to denounce Senator Joe McCarthy, enraged Truman, to the point that Truman poured every bit as much energy into defeating Ike as Obama did to defeating Trump.

But Election Day changed all that. Truman had taken office in 1945 upon Franklin Roosevelt’s death with no preparation whatsoever for managing the immense burden of the office. In the post-war, nuclear age, ignorance was dangerous, and so with Eisenhower’s victory, Truman instructed members of the White House staff to do everything they could to help the incoming administration, and invited Ike to visit before the inauguration so Truman could brief him on what would confront him on his first day. When Eisenhower came to the White House on November 18, it was only the fourth meeting of its kind in history, and like the first—between Jefferson and Adams—it produced only acrimony. The second and third such meetings were between Herbert Hoover and Roosevelt, and those were positively toxic.

But this time there was important business to discuss, particularly the war in Korea. Truman came away from the meeting convinced that Eisenhower was “awestruck by the long array of problems and decisions the President has to face.” Ike admitted to no such reaction, and relations between the two men remained hostile until both were out of office a decade later, and reconciled in the twilight of their long public lives.

Eight years later, Eisenhower, for his part, kept up the tradition. Once again, the incoming and outgoing presidents were hardly friendly: Before election day in 1960, Ike told one Oval Office visitor, as he jabbed a finger toward his desk chair: “Listen, dammit, I’m going to do everything possible to keep that Jack Kennedy from sitting in this chair.” John F. Kennedy was just as harsh, referring to Eisenhower privately as “that old a—hole.” But upon Kennedy’s victory, Eisenhower invited him to the White House twice for briefings and discussion. He too told his staff to help the incoming team in any way they could. They met in the Oval Office to discuss how the national security apparatus was arranged, the roles of members of the White House staff, how to handle the cabinet. “No easy matters will ever come to you as President,” Eisenhower warned Kennedy. “If they are easy, they will be settled at a lower level.” He urged Kennedy to avoid any reorganization until he had learned for himself the nature of the job. “I pray that he understands it,” Eisenhower wrote that night. “Certainly his attitude was that of a serious, earnest seeker for information.”

Yet another handoff between political enemies occurred in 1968, after Richard Nixon narrowly defeated Lyndon Johnson’s vice president Hubert Humphrey. Here too there was ample reason for the two men to be at each other’s throats: In the final weeks of the campaign, Johnson had obtained evidence that Nixon was secretly undermining the Vietnam peace talks in order to avoid an October breakthrough that would have boosted Humphrey’s candidacy and sealed Johnson’s legacy. Yet once again, the meetings after Nixon’s victory were cordial, businesslike, and strangely prescient. At one point, Nixon sat on the sofa, Johnson in his king-size rocker. The retiring president talked about secrecy, of all things. “I will warn you now, the leaks can kill you,” Johnson said, and he urged Nixon to tear out the recording system that Johnson had used in the Oval Office.

And so it went through the years, including when George W. Bush invited the entire President’s Club to meet the newest member in January of 2009. Both Presidents Bush, Jimmy Carter and Bill Clinton all assembled for lunch with President-elect Barack Obama. “We want you to succeed,” Bush told him. “All of us who have served in this office understand that the office transcends the individual.”

Obama echoed those words the day after the election, in anticipation of meeting face-to-face the man he had wholeheartedly denounced in the last weeks of a bitter race. “One thing you realize in this job is that the presidency—or the vice presidency—is bigger than all of us,” Obama said.

As the President-elect is about to discover.

Nancy Gibbs is the editor-in-chief of TIME and, along with Michael Duffy, the author of The Presidents Club: Inside the World’s Most Exclusive Fraternity.