President Trump, confronted by mounting pressure for an independent investigation into his associates' ties to Russia, unleashed a startling and unsupported attack on his predecessor Saturday, accusing former President Obama of wiretapping his phones during the 2016 election.
Trump's flurry of Twitter messages, which was supported by no evidence, was bizarre even for a White House with a history of broadsides against political opponents. Throughout the day, administration officials refused to offer any explanation for the president's missive or any evidence to back it up.
"Just found out that Obama had my 'wires tapped' in Trump Tower just before the victory. Nothing found," Trump wrote on Twitter Saturday, adding: "This is McCarthyism!"
"How low has President Obama gone to tapp [sic] my phones during the very sacred election process. This is Nixon/Watergate. Bad (or sick) guy!" Trump wrote in a series of four tweets from Florida, sent around breakfast time.
The charges leveled by Trump echoed an unsubstantiated story line circulating on right-wing media. The attack came after a stressful 48 hours for Trump during which Atty. Gen. Jeff Sessions announced that he was stepping aside from any role in supervising the investigation of Russian interference in last year's presidential election, a subject about which Trump has shown extreme sensitivity. Trump had publicly said he did not believe Sessions should recuse himself and reportedly was angered by the decision.
As the White House refused to respond to mounting questions from journalists and lawmakers about Trump's charges of wiretapping, his public schedule for the weekend shifted. A relatively light agenda was replaced with one that includes meetings with Sessions, Secretary of Homeland Security John Kelly and senior advisors Steve Bannon, Stephen Miller and Don McGahn.
Veterans of the Obama administration accused Trump of lying outright.
"A cardinal rule of the Obama administration was that no White House official ever interfered with any independent investigation led by the Department of Justice," Kevin Lewis, a spokesman for the former president, said in a statement.
"Neither President Obama nor any White House official ever ordered surveillance on any U.S. citizen," Lewis said. "Any suggestion otherwise is simply false."
A former senior U.S. national security official called it "irresponsible, extraordinary and dangerous" for a sitting president to accuse his predecessor of wiretapping "based on uncorroborated information in a politically oriented publication."
Trump's charges confused lawmakers from both parties, who pointed out that if federal officials had legally wiretapped Trump's offices, they would have done so with the blessing of a judge who would have been required to find credible evidence that someone there either was acting as a foreign agent or engaging in criminal behavior. Otherwise, such a wiretap would have been illegal.
Either way, said Republican Sen. Ben Sasse of Nebraska, Trump needs to be more forthcoming immediately.
"The president today made some very serious allegations, and the informed citizens that a republic requires deserve more information," Sasse said in a statement.
It would be highly unusual for a sitting president to be aware of a surveillance request, as Trump charged was the case with Obama. By blaming Obama directly, Trump accused the former president of reaching into a federal investigation or signing off on an illegal wiretap, which is a felony. Trump's tweets Saturday were a marked departure from the more subdued, statesmanlike tone he had tried to move toward during his address to a joint session of Congress on Tuesday.
The charges tracked with unfounded reports being circulated among White House officials by conservative radio host Mark Levin and the Breitbart News website, which Bannon led before joining Trump's campaign last summer.
U.S. intelligence officials concluded in January that Russia had launched covert actions and cyberattacks to damage Hillary Clinton's candidacy and help Trump win. But it is unclear if those actions were coordinated with people in Trump's inner circle.
In the meantime, a pattern of Trump officials downplaying their contacts with Russia has stirred calls for further investigation.
Sessions did not disclose meeting Russian Ambassador to the U.S. Sergey Kislyak when asked about contacts with Russians during his Senate confirmation hearing.
Trump's former national security advisor, Michael Flynn, resigned last month when it was disclosed that he had misled Trump administration officials about conversations he had with Kislyak about U.S. sanctions against Russia before Trump's inauguration.
Democratic lawmakers pounced on Trump's allegations.
"If there is something bad or sick going on, it is the willingness of the nation's chief executive to make the most outlandish and destructive claims without providing a scintilla of evidence to support them," Rep. Adam Schiff (D-Burbank), the top Democrat on the House Intelligence Committee, said in a statement.
President Richard M. Nixon was convinced that his predecessor, Lyndon B. Johnson, had wiretapped his phone and placed a bug on his plane during the last two weeks of the 1968 campaign. The FBI had never gone that far, but Nixon had reason to be concerned.
The FBI knew Republicans had worked with South Vietnamese officials to scuttle peace talks Johnson was holding and made assurances that Nixon would give them a better deal, and the bureau had Nixon fundraiser Anna Chennault under surveillance.
"I see echoes with the past," Ken Hughes, a researcher at the University of Virginia Miller Center, a think tank that studies the presidency, said in an interview.
"It is clear that Trump is very defensive and he is very worried," said Hughes, who wrote a book on the Republican interference in the Vietnam peace talks.
"It might mean the investigation into the Russian interference in our election will expose other things he wants to keep hidden," Hughes said.
After sending out several tweets accusing the previous administration of gross misconduct, Trump had something else on his mind:
"Arnold Schwarzenegger isn't voluntarily leaving the Apprentice, he was fired by his bad (pathetic) ratings, not by me. Sad end to great show," Trump wrote.