President Trump said he will “most likely” nominate Army Secretary Mark T. Esper to be his next Pentagon chief, potentially creating some stability after acting defense secretary Patrick M. Shanahan’s surprise decision to withdraw from consideration for the job and leave government service.

“That’s what I’m thinking about doing,” Trump said Tuesday, adding that he will make his choice “pretty soon.”

The comments came after a tumultuous day in which Shanahan stepped aside after The Washington Post and other media outlets detailed past domestic abuse in his family, including an incident in which Shanahan’s son attacked his own mother with a baseball bat.

Esper, 55, was named by the president as the acting replacement for Shanahan on Tuesday afternoon. He is expected to take over as acting defense secretary on Monday, ahead of a meeting of NATO defense ministers in Brussels next week.

But it wasn’t clear whether Trump wanted Esper to serve as defense secretary permanently. Some Republicans have floated other names, including Robert Wilkie, a former Pentagon official who is secretary of Veterans Affairs.

Esper brings to the acting defense secretary job a broad array of government experience that includes time on Capitol Hill, in the Pentagon and in the private sector. Married with three adult children, he has lived in Northern Virginia for years and served in the active-duty Army and Virginia National Guard for 25 years, after graduating from the U.S. Military Academy at West Point, N.Y., in the same 1986 class as Secretary of State Mike Pompeo.

As Army secretary, Esper has focused on modernizing the service and preparing it for potential conflict with large competitors such as China, establishing the Army’s new Futures Command in Austin.

Esper also has shown independence on some subjects. Under questioning on Capitol Hill last year, he and Gen. Mark A. Milley, the Army’s top officer, said they had no indication that transgender service members in the military were causing any disruption, after Trump called for a ban.

“Nothing has percolated up to my level,” Esper said in a Senate Armed Services Committee hearing in April 2018.

Speaking about his leadership style, Esper told an audience in Washington last November that while building consensus is “great,” he also wants to hear alternative viewpoints before making decisions.

“I think consensus gives you suboptimal options,” Esper said at the American Enterprise Institute. “I’m not looking for consensus opinions. Because some of the best decisions we made in the last, you know, 12 months have been because one person spoke up and presented an alternative idea that didn’t comport with the consensus.”

Richard Fontaine, the chief executive of the Center for a New American Security in Washington, said he has known Esper for about 15 years and believes he would be a good choice for defense secretary. But Fontaine also acknowledged that Esper faces challenges, considering how quickly personnel changes have been required.

“The jump from really almost anything to secretary of defense is a big one because of the extremely broad nature of the portfolio,” Fontaine said. “It includes overseeing operations, being a major public figure, dealing with Capitol Hill and serving as a diplomat of sorts.”

Esper, in an interview with The Washington Post last year, said he supports the president and considered it appealing to serve as Army secretary because of the team that had been assembled under then-defense secretary Jim Mattis. He has sometimes downplayed the effects of decisions made by the Trump administration, only to acknowledge issues when pressed by lawmakers.

In March, Esper told the Senate Armed Services Committee that the Trump administration’s decision to reprogram $1 billion from Army personnel accounts to pay for parts of the president’s southern border wall would not affect military readiness. But under questioning from Sen. Jack Reed (D-R.I.), he acknowledged that the money could have been spent on other military priorities, such as upgrading Army aviation.

“The needs always exceed the means, so yes, we could have used that money as the other services to continue to improve our readiness,” Esper said.

One spot that will likely face scrutiny during a confirmation hearing is Esper’s past work at Raytheon, where he served as a top lobbyist for about seven years.

Noah Bookbinder, the executive director of Citizens for Responsibility and Ethics in Washington, said in a statement Tuesday that Esper's ethics agreement and his ability to follow it will be something to watch as he steps into a new role.

“Already this week, Raytheon has won multiple government contracts worth hundreds of millions of dollars,” Bookbinder said. “While Esper may not have had sway over these types of deals as Secretary of the Army, as acting Secretary of Defense he will have potential influence over such deals, as well as over the controversial proposed merger of Raytheon and [United Technologies Corp.] to become the second largest defense company in the U.S.”

Fontaine said that Esper’s time at Raytheon will not necessarily impact him negatively, especially given his government experiences. They include serving as a deputy assistant secretary of defense under President George W. Bush, a national security adviser to then-Senate Majority Leader Bill Frist (R-Tenn.) and as legislative director to then-Sen. Chuck Hagel (R-Neb).

Lawmakers, including some Democrats, have so far appeared open to the idea of Esper serving as defense secretary.

Adam Smith (D-Wash.), the chairman of the House Armed Services Committee, said in a statement Tuesday that he is confident Esper can carry out the Pentagon’s plans “in a way that is insulated from outside influence and political considerations.”

“I have known Esper for years, both as a staff member on the Hill and in private industry, and believe the Department would benefit from his leadership,” Smith said.

Sen. Angus King (I-Maine), speaking Wednesday on CNN, said he has been impressed with Esper as Army secretary.

“He knows the Pentagon. He knows the military. I think he starts at a good place,” King said. “But I’m going to reserve judgment until we have a hearing. The usual question I ask is, ‘Will you tell the president the truth?’ If he gives me a good answer to that, then we’re part of the way there.”