David Shulkin, President Trump's choice to lead the Department of Veterans Affairs, faces the unique challenge of overhauling a system he's spent the past two years defending. And with a boss who spent more than a year on the campaign trail shaming VA officials for their recent failures, Shulkin may not have room for error when he tackles problems in one of the largest and most complex organizations in the world.

The VA's current undersecretary for health is expected to sail through the confirmation process, unlike many of Trump's other Cabinet picks. Sen. Johnny Isakson, R-Ga., chairman of the Senate Veterans Affairs Committee, concluded Shulkin's remarkably amiable confirmation hearing on Feb. 1 by noting the lack of "monkey business" members had deployed against the nominee.

Tasked with implementing the president's ambitious 10-point reform plan, Shulkin will encounter his biggest battles only after getting confirmed. An engorged bureaucracy, short-staffed medical teams, entrenched employees and a rapidly changing veteran population would make Trump's vision difficult to implement under the best of circumstances. And a bitterly divided Congress could complicate reforms even further.

Rep. Phil Roe, chairman of the House Veterans Affairs Committee, said one of the first steps toward achieving Trump's goals will be to pass laws that give Shulkin more authority to remove people within the VA.

"He's very limited now with what he can do," Roe told the Washington Examiner. "We've tried with [former VA] Secretary [Bob] McDonald to make it easier for him to fire people that are nonperforming, and I think certainly we'll be able, with President Trump, to provide the legislation that'll allow them to do that, while being fair to the employee. You want to be fair to both."

Federal employees' unions have pressured members of Congress to drop or water down legislation during previous attempts to simplify the process by which bad VA employees can be fired, and their opposition is unlikely to fade under Shulkin.

"They are going to fight any type of reform that instills more accountability in the VA," said Dan Caldwell, legislative director of Concerned Veterans for America, of federal employees' unions.

"They've made that very clear: They don't support reforming the VA in any major way," Caldwell added. "That is going to be the biggest source of resistance."

Not only did Trump call on Congress to give Shulkin expanded firing authority in his 10-point plan, he also vowed to "[u]se the powers of the presidency to remove and discipline the federal employees and managers" who misbehave. During the Obama administration, after a wait-time scandal that covered up delays in healthcare at more than 100 VA facilities around the country, only a handful of employees were fired for their involvement.

Beyond unions, Shulkin will also face resistance from officials who have worked at the VA for decades and who won't be eager to see major changes, said Scott Davis, a VA whistleblower in Atlanta.

"I think the biggest challenge Dr. Shulkin will face at VA is dealing with unscrupulous career bureaucrats within the organization that have been there for 20, 30-plus years that believe they can just wait him out," Davis told the Washington Examiner. "These people have seen secretaries come and go, and they don't fear any sense of accountability."

That's why Shulkin must "set the tone that the foolishness of the past won't be tolerated" immediately upon taking office, Davis added.

Trump announced during the transition that he planned to consider a "public-private option" for VA reform that would expand veterans' access to care outside the VA system. The basic principle of giving veterans the ability to choose private care has been a GOP goal for years, but VA officials have resisted implementing a two-year pilot program that was designed to increase choice in the wake of the wait-time controversy.

"We have to redo choice, there's no question," Roe said of the program. The Tennessee Republican highlighted the plight of veterans who live in rural towns where the local VA system may be understaffed.

"They desperately need the choice program to work, because they don't have all the needed physicians and specialists at the VA hospital in their area," Roe said.

The choice program will expire this year. It allows only those veterans who live too far from a VA hospital or who are unable to secure a timely appointment to bypass the VA system and seek private care. Trump has suggested he wants to give every veteran that option.

Like several of Trump's other Cabinet secretaries, Shulkin could come into a bureaucracy filled with officials who are hostile to the new president's agenda.

Davis pointed to former Acting Attorney General Sally Yates, who lost her position after taking a public stand against Trump's refugee-related executive action.

"When veterans were dying at VA hospitals, they did absolutely nothing. That is blatant hypocrisy," Davis said of the Obama-era Justice Department.

The VA whistleblower said Trump's attorney general will need to do a better job of going after VA employees who are criminally negligent on the job.

While Caldwell said he is encouraged by the people Shulkin has consulted since receiving the nomination — a list that he said included Newt Gingrich and former VA officials from the Bush administration — he warned that bureaucrats and unions could easily grind Shulkin's progress to a halt.

"I think that Dr. Shulkin is unfortunately going to face some resistance from the career bureaucracy, meaning the people that are not leaving with the Obama administration," Caldwell said.

Trump has spent the early days of his presidency focusing on jobs and immigration, but veterans advocates remain hopeful that he will deliver on his promises to make VA reform a priority.

"If his administration states clearly where they would like to see the VA go ... then I think we've got a lot on our side," Roe said.

Davis, who still works at the VA, said he expects to see changes under Shulkin's leadership, even if many view Shulkin as a VA insider.

"I think that I am cautiously optimistic that we will see some level of improvement," Davis said. "But I think it's also going to be incumbent on the president to hold Dr. Shulkin and others in his Cabinet responsible."