Exactly what Michael Cohen told Robert Mueller has been among the most unnerving unknowns for those closest to the president ever since Trump’s longtime fixer began cooperating with the Russia probe in the summer. “If anyone can blow up Trump, it’s him,” a former West Wing official told me in June. The detonation began on Thursday, when Cohen pleaded guilty to lying to Congress, accompanied by a detailed plea agreement, a new set of facts that begin to fill in a picture. To the Trump camp, it looked ominous. “The Cohen news is very bad,” a former White House staffer said.

The fear in Trumpworld is that Mueller may have laid a perjury trap for the president, the former staffer said. Mueller waited until after Trump submitted written answers under oath to the special counsel’s office—some of which reportedly included responses to questions about Trump Tower Moscow—before revealing the evidence prosecutors had gathered to secure Cohen’s plea. “Trump was totally caught off guard by the Cohen plea,” the source said.

Indeed, Trump’s erratic responses suggest he was surprised by the news. At first, his lawyer Rudy Giuliani released a blistering statement saying Cohen is “a proven liar who is doing everything he can to get out of a long-term prison sentence for serious crimes of bank and tax fraud.” In comments he made to reporters before departing for the G20 summit in Argentina, Trump called Cohen “weak” and accused him of “making up a story.” But hours later, Giuliani changed tacks, telling The New York Times that Trump’s sworn answers to Mueller matched Cohen’s version of events. “Why would the president come out and say Cohen lied?” the former staffer said.

In the days leading up to Cohen’s plea, Trump’s legal team had grown increasingly annoyed with the special counsel’s office for stonewalling. Giuliani vented to a friend that Mueller’s office stopped communicating with him after he delivered Trump’s answers. “They’ve gone dark,” the friend who spoke with Giuliani said. “Rudy is extremely frustrated. He thinks Mueller is acting like some junior U.S. attorney who’s got his panties in a wad and doesn’t want to talk to you.” Giuliani also complained that Mueller is delaying submitting his report to the Justice Department until the Democrats have taken control of the House of Representatives in January. (Giuliani did not respond to a request for comment.)

Cohen’s plea also re-ignited fears that the president’s son, Don Jr., will be next to be indicted. “Don’s been telling people he’s very worried after today,” a source said. (Don Jr.’s attorney did not immediately respond to a request for comment.) Mueller now appears to be driving the West Wing agenda, with the principals in a reactive crouch; there’s a sense of loss of control. “It’s an untethered situation,” a person close to the president said.

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