President Trump's son-in-law and senior adviser Jared Kushner welcomed special counsel Robert Mueller's appointment, taking it as a sign that the Senate Select Committee investigation into Russian influence in the 2016 election was losing purchase.

A new account of the White House reaction to the Justice Department's naming of former FBI Director Mueller to lead the investigation of the Trump campaign reveals how some aides took it in stride.

"This is great," Kushner, 39, said as White House aides drafted a response to the coming announcement. "We're not going to have to worry."

But then-White House communications director Mike Dubke, 59, was alarmed by Kushner's rosy outlook. "You don't understand how any of this works," Dubke said to Kushner. "These will all go on simultaneously. There is going to be Mueller; there's going to be investigations in the House, in the Senate. They are coming after you."

The account is included in a new book by Washington Post reporters Philip Rucker and Carol Leonnig, A Very Stable Genius: Donald J. Trump's Testing of America.

Adviser Hope Hicks drafted the statement, printed a copy in size 16 font for Trump, and incorporated his edits as aides stood around her. Hicks, 31, a savvy, trusted operator who was not as sanguine as Kushner, already had a lawyer, the book reports.

Mueller inspired reverence among his peers and colleagues for his exacting and tireless efforts, and he demanded as much from his staff. Deputies were accustomed to finding notes from him on their desks when they arrived at work at 7 or 8 a.m., wondering where they were and asking them to find him once they arrived. Former federal prosecutor Chuck Rosenberg, 59, "would walk on hot coals" for him, the book reports.

But the Trump defense team had a different view. The lawyers were afforded so little contact that they questioned how much work he was doing. Giuliani said he "always had a feeling they were hiding him." Trump attorney John Dowd, Giuliani said, told him, "Well, he's not really on top of the case. He's kind of like delegating it."

Similarly, officials at the Justice Department who at times dealt with his office cast Mueller as the wizard from the 1939 film The Wizard of Oz, delivering his edicts via aggressive aides while behind the curtain.