When last they saw each other six weeks ago after the ceremonial passing of power, President Trump and former President Barack Obama parted with smiles and handshakes. But it did not take long for the surface bonhomie to degenerate into a fierce and public clash unlike any other in modern times.
While Mr. Obama has remained quiet for the most part, some of his closest loyalists moved into opposition mode, leading what some only half-jokingly call “the resistance.” Mr. Trump, convinced that Obama holdovers still in government are trying to sabotage his presidency, took the conflict nuclear over the weekend by accusing his predecessor of bugging his telephones last year.
Mr. Trump provided no proof, and the charge was quickly dismissed by intelligence veterans and, indirectly, the F.B.I., but that did not make it any less sensational or any less historic. Never in recent generations has the natural friction between current and past presidents spilled over into such a public spectacle. If sustained, it could fray the institution of the presidency, further erode the public’s already low confidence in the nation’s leadership and leave both allies and enemies with the impression of an America at war with itself.
Perhaps it should be no surprise that it came to this between the 44th and 45th presidents. During last year’s campaign, Mr. Obama called Mr. Trump a “con artist and a know-nothing” who could not be trusted with the nuclear codes. Mr. Trump called Mr. Obama “the worst president in the history of the United States” after spending years questioning whether he had been born in the United States. They put that rancor aside for a cordial meeting after the election, but that barely veiled the chasm between them in terms of personality, politics and policy.
“We’re in a unique period,” said Newt Gingrich, the Republican former House speaker who has been an outside adviser to the new president. “Trump is a genuinely disruptive figure who threatens everything Obama stands for.”
Mr. Obama’s camp insisted they are simply defending their legacy. “It takes two people to duel, and only one seems to be aiming his weapon,” said Jennifer Psaki, White House communications director under Mr. Obama. “The uniqueness of the time is the fact that you have one unhinged and misinformed sitting president pointing his gun at a former. That is unprecedented.”
Denis R. McDonough, Mr. Obama’s last White House chief of staff, said the former president’s team could not remain silent in the face of false assertions. “What I have witnessed in recent days is former colleagues speaking out against untruths when needed,” he said. “That is best characterized as not backing down from attacks; it is not seeking out conflict.”
But inside the Trump White House, it has become an article of faith that people seeded throughout the government by Mr. Obama have been leaking everything they could get their hands on to damage the new president.
“I think that President Obama is behind it, because his people are certainly behind it,” Mr. Trump said in a recent interview with “Fox & Friends.” “And some of the leaks possibly come from that group, you know, some of the leaks, which are really very serious leaks, because they’re very bad in terms of national security.”
Other presidents have endured fractious relations. After leaving office, Herbert Hoover regularly castigated Franklin D. Roosevelt, who ostracized his predecessor. Harry S. Truman was so estranged from Dwight D. Eisenhower that they did not speak during a frosty ride to the 1953 inauguration. Ronald Reagan publicly blamed his woes on the mess he said Jimmy Carter had left him, just as Mr. Obama from time to time pointed the finger at George W. Bush.
But none of those moments compared to what America has seen in recent days. “Trump is on new ground in going after Obama,” said the historian Robert Dallek, who has written acclaimed books on John F. Kennedy, Lyndon B. Johnson and Richard M. Nixon. Most presidents have publicly ignored their predecessors “until we get to Trump,” he added. “He is either ignorant of recent presidential history or simply doesn’t care.”
The closest analogue in modern times may have been Johnson and Nixon, both presidents who favored secret wiretapping. In his last days in office, Johnson was furious at Nixon after wiretaps revealed that a Republican intermediary seemed to be trying to undercut possible peace talks before the 1968 election. For his part, Nixon was convinced that Johnson had bugged him. Yet neither Johnson nor Nixon publicly aired those grievances at the time.
“The Nixon tapes show that Nixon always thought that Johnson taped his 1968 campaign, and possibly Nixon himself,” said Luke A. Nichter, a leading scholar of Nixon’s secret Oval Office tapes at Texas A&M University. “Nixon said that it was J. Edgar Hoover who told him this. However, based on the available records, the closest to wiretapping Nixon that L.B.J. ever came was monitoring the phone calls out of Spiro Agnew’s campaign plane.”
Before last year’s campaign, Mr. Obama told advisers that he was inclined to keep quiet after leaving office to give his successor a chance to govern, much as Mr. Bush did for him. But he expected that successor to be Hillary Clinton or even Jeb Bush or Marco Rubio. Mr. Trump was a different story, and Mr. Obama concluded he would speak out if he felt the nation’s ideals were under threat.
Ten days into the new administration, when Mr. Trump issued his first temporary travel ban on visitors from seven largely Muslim countries and cited Mr. Obama’s own actions as precedent, the former president did just that in a statement saying he “fundamentally disagrees with the notion of discriminating against individuals because of their faith or religion.”
His team did not wait even that long. The day after the inauguration, former Obama administration officials, including John Kerry, whose tenure as secretary of state had just ended, joined a women’s march in Washington protesting Mr. Trump. Other officials appeared on television talk shows and newspaper op-ed pages to speak out against the new president’s policies.
Mr. Trump’s team has been angered by the criticism but even more by what they see as the enemy within. With so few of his own political appointees in place, much of the government is still operating with acting officials, some held over from the Obama administration. Moreover, the federal Civil Service, while officially neutral politically, is not dominated by Trump supporters, judging by vote results in Washington and its suburbs.
So when Mark Levin, the conservative radio host, contended that Mr. Obama had targeted Mr. Trump for surveillance in what he called a “silent coup,” an assertion picked up by Breitbart News, the former website of the White House chief strategist Stephen K. Bannon, it struck a chord. Along with reports that in Mr. Obama’s last days in office his administration changed the rules on distributing intelligence and made a point of spreading information about Mr. Trump’s team and Russia to different parts of the government to “preserve” it, the wiretapping allegation pushed Mr. Trump over the top.
“It’s a sign of how deeply frustrated he is,” Mr. Gingrich said. “They have a much bigger assault against them than people have had in the past.”
And so, Mr. Gingrich added, Mr. Trump needs to figure out how to get control of his own bureaucracy. “He’s not going to survive,” he said, “unless he profoundly rethinks what they’re doing and how they’re doing it.”