Trump declared Jackson’s nomination on Twitter at 5:31 p.m. The tweet was big news — not just to the public, but to some senior aides, according to one White House official.

The chaos — by now a typical part of the president’s management style — has for months upended Kelly’s attempts to ensure that an unorthodox White House adheres to traditional processes. But while White House aides are left unpacking the day’s events, the drama at the VA is just beginning.

Deputy Secretary Thomas Bowman, a Trump appointee who is the agency’s No. 2, is widely expected to leave soon, either by choice or by force. Kelly and other aides wanted Bowman gone before Shulkin left to avoid installing the deputy at the helm, even temporarily. Bowman had pushed back on broad privatization efforts, leading Trump to berate him in an Oval Office meeting for his lack of loyalty.

Trump got around the Bowman problem by naming Robert Wilkie, an undersecretary at the Department of Defense, to the temporary job. A Capitol Hill veteran and member of Trump’s transition team, Wilkie is a former senior adviser to Sen. Thom Tillis (R-N.C.), who supports expanding service members’ access to private doctors.

“He’s got a department that’s in turmoil. It’s in crisis. There’s warfare there,” said Anthony Principi, who led the agency under President George W. Bush. “And you have an acting secretary who doesn’t know the VA.”

But if and when Bowman departs, Wilkie will be left with a shallow bench at an agency already paralyzed by political mistrust, some veterans’ advocates say. The VA’s health and benefit agencies — which administer tens of billions of dollars in health programs, pensions, survivor benefits and other forms of assistance to some 9 million service members — have been without Senate-confirmed officials since the Obama administration.

Veterans Affairs is the second-largest federal agency, behind only the Department of Defense, with 377,000 employees. And it has proven unwieldy even when led by highly decorated, experienced administrators such as Eric Shinseki, a retired four-star Army general who resigned during the Obama administration amid a scandal over lengthy wait times and faulty scheduling practices for medical appointments.

Shinseki was followed by Bob McDonald, an Army veteran and former Procter & Gamble CEO. Shulkin, McDonald’s successor, was the first nonveteran to lead the VA.

As recently as two weeks ago, the Trump White House was still making overtures to potential candidates for the top job, according to a person with direct knowledge of the inquiries. Trump reportedly agonized over the decision, changing his mind several times, a senior administration official said.

“Instead of going through the paces to convince the best possible person to take this job, they’re going with the person who’s still on active duty in the Navy and can’t say no to the commander in chief,” said one Obama White House aide, who spoke highly of Jackson as a doctor and individual. “You could look at it as them giving up trying to find a competent commander or manager to fix the problems.”

Shulkin had come under fire after a VA inspector general’s report accused him of improperly accepting tickets to the Wimbledon tennis tournament and using his agency staff to arrange a sightseeing tour of Denmark and England. He repaid the VA for the trip. The longtime hospital administrator, who was engaged in open warfare with conservatives in the department intent on privatizing the VA, contended he was set up.

Veterans’ groups remained loyal to Shulkin, whom they saw as their best line of defense of against privatization. During his campaign, Trump made promises that veterans would be allowed to seek medical treatment outside the VA’s system, statements taken by some to mean a step toward handing the system to commercial companies to manage.

Jackson, while well-liked by both Republicans and Democrats, is a cipher on privatization and other policy issues. With no agency experience to speak of, veterans suspect he could be installed as a figurehead, leaving lower-level appointees to steer the agency toward privatization.

“He’s a blank slate. Nobody knows really anything about his competency or capacity for this job,” said Paul Rieckhoff, CEO of Iraq and Afghanistan Veterans of America. “We especially know that being a veteran doesn’t qualify you to run the VA any more than being a soldier qualifies you to run the DoD.”

Principi urged Jackson to move quickly on his own agenda.

“The new secretary, really, if he wants to accomplish anything, has to hit the deck running and has to bring in some very, very good people,” he said. “I hope and pray he’s a success. Because if he’s not, American veterans are going to be the losers.”