Jim Mattis Compared Trump to ‘Fifth or Sixth Grader,’ Bob Woodward Says in Book

President Trump so alarmed his defense secretary, Jim Mattis, during a discussion last January of the nuclear standoff with North Korea that an exasperated Mr. Mattis told colleagues “the president acted like — and had the understanding of — a ‘fifth or sixth grader.’”

At another moment, Mr. Trump’s aides became so worried about his judgment that Gary D. Cohn, then the chief economic adviser, took a letter from the president’s Oval Office desk authorizing the withdrawal of the United States from a trade agreement with South Korea. Mr. Trump, who had planned to sign the letter, never realized it was missing.

.. book by Bob Woodward that depicts the Trump White House as a byzantine, treacherous, often out-of-control operation — “crazytown,” in the words of the chief of staff, John F. Kelly — hostage to the whims of an impulsive, ill-informed and undisciplined president.

.. The White House, in a statement, dismissed “Fear” as “nothing more than fabricated stories, many by former disgruntled employees, told to make the president look bad.”

.. Mr. Woodward portrays Mr. Mattis as frequently derisive of the commander in chief, rattled by his judgment, and willing to slow-walk orders from him that he viewed as reckless.

.. Mr. Trump questioned Mr. Mattis about why the United States keeps a military presence on the Korean Peninsula. “We’re doing this in order to prevent World War III,” Mr. Mattis responded, according to Mr. Woodward.

.. In April 2017, after President Bashar al-Assad of Syria launched a chemical attack on his own people, Mr. Trump called Mr. Mattis and told him that he wanted the United States to assassinate Mr. Assad. “Let’s go in,” the president said, adding a string of expletives.

The defense secretary hung up and told one of his aides: “We’re not going to do any of that. We’re going to be much more measured.” At his direction, the Pentagon prepared options for an airstrike on Syrian military positions, which Mr. Trump later ordered.

.. another layer to a recurring theme in the Trump White House: frustrated aides who sometimes resort to extraordinary measures to thwart the president’s decisions — a phenomenon the author describes as “an administrative coup d’état.” In addition to Mr. Mattis and Mr. Cohn, he recounts the tribulations of Mr. Kelly and his predecessor, Reince Priebus, whose tensions with Mr. Trump have been reported elsewhere.

.. Mr. Cohn, Mr. Woodward said, told a colleague he had removed the letter about the Korea free trade agreement to protect national security. Later, when the president ordered a similar letter authorizing the departure of the United States from the North American Free Trade Agreement, Mr. Cohn and other aides plotted how to prevent him from going ahead with a move they feared would be deeply destabilizing.

.. Last January, Mr. Woodward writes, Mr. Dowd staged a practice session in the White House residence to dramatize the pressures Mr. Trump would face in a session with Mr. Mueller. The president stumbled repeatedly, contradicting himself and lying, before he exploded in anger.

.. Mr. Woodward told Mr. Trump he interviewed many White House officials outside their offices, and gathered extensive documentation. “It’s a tough look at the world and the administration and you,” he told Mr. Trump.

“Right,” the president replied. “Well, I assume that means it’s going to be a negative book.”