Mr. Trump has long been obsessed with loyalty, a view only exacerbated by his impeachment and the various investigations over the last three years that have convinced him that he is surrounded by a deep-state enemy within that is leaking, lying and sabotaging his presidency.

He has also been frustrated by the decision-making process of government, aggravated at competing centers of power that have shaped the modern presidency but have, in his view, hindered his ability to enact policies.

With a more loyal team in place, he hopes to make more progress on initiatives that have been slow-walked by institutional inertia or resistance like tougher rules on trade and immigration. But it could mean less dissent and less open debate with surviving officials fearing the loss of their jobs if they are seen as stepping out of line.

From the beginning, his administration has been a turnstile of people who fall in and out of favor with the president. Including those with “acting” designations, he is on his third chief of staff, his fourth national security adviser, his fourth defense secretary, his fifth secretary of homeland security, his sixth deputy national security adviser and his seventh communications director.

According to data compiled by Kathryn Dunn Tenpas, a senior fellow at the Brookings Institution, turnover among what she calls Mr. Trump’s “A team,” meaning his senior staff, has hit 82 percent, more in three years than any of the previous five presidents saw in their first four years. Moreover, the Trump administration has been notable for a high level of serial turnover, with 38 percent of the top positions replaced more than once.

“Many key departments and White House entities have been hollowed out,” Ms. Tenpas said. The president has thus been left with acting officials in many key areas. “He seems completely unbothered,” she said. “He claims that actings give him flexibility, but fails to see that temporary leaders cannot advance his policies nearly as well as a Senate-confirmed appointee who has the stature and all the powers to do so.”

While some of the reliance on acting officials owes to a dysfunctional Senate confirmation process, Mr. Trump seems to prefer to keep senior advisers on edge as to whether they will keep their job. Mick Mulvaney, his acting White House chief of staff, a position that does not require Senate confirmation, is finishing his 14th month with an “acting” in front of his title for no reason that has ever been publicly articulated and he may be forced out without ever having been granted the full title.