Is John Kelly ready for the White House?

Retired U.S. general John Kelly is a battle-hardened commander who is expected to bring military-style discipline to U.S. President Donald Trump's roiling White House when he takes over as the new chief of staff on Monday.

But it's unclear how Kelly, who is blunt-spoken and has demonstrated little patience for nonsense, will work with an administration rife with infighting and a commander-in-chief who prefers chaos to order.

For the first few months, they will get along just fine- Kevin Eckery, political strategist

"For the first few months, they will get along just fine," says Kevin Eckery, a crisis management consultant and political strategist based in Sacramento, Calif. "Ultimately, the problem isn't with the chief of staff, the problem is with the president  — he does not have a disciplined style."

Outgoing chief of staff Reince Priebus, the former chair of the Republican National Committee, was brought in as a well-connected Washington insider with close congressional contacts. But he was never a fit with Trump, Eckery says.

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"While I certainly think that Reince shared [Trump's] agenda, I also think that as someone who was more associated with the institutional party, and as someone also with a pretty good reputation for being a straight shooter … [he] was just a square peg in a round hole anyway."

And if there is dysfunction between the president and the chief of staff, "that is only going to cascade through the system," Eckery says.

'Nation under attack'

Enter the 66-year-old Kelly, a career military man with limited political and legislative experience. The 40-year Marine Corps veteran served three tours in Iraq and led the U.S. Southern Command before being appointed by Trump to head the Department of Homeland Security.

In that role, he has taken the lead on some of Trump's most controversial policies, including executive orders suspending the admission of refugees and temporarily barring visitors from several Muslim-majority nations. Those orders have been stripped down by courts pending a Supreme Court review this fall.

Just days after taking office, Kelly had to lead the agency as it dealt with the chaos and confusion that ensued at airports in the U.S. and around the world. He defended the orders to reporters and lawmakers and insisted he indeed had been part of the decision-making process.

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Kelly supports Trump's Mexico border wall plan and has stood up in Congress to defend the Trump administration's approach to immigration enforcement.

In a speech to Congress in April, he famously declared that the U.S. is "a nation under attack … every single day," and bluntly challenged lawmakers to either change the laws or "shut up."

Kelly is the highest-ranking officer to lose a child in combat in the U.S.'s so-called war on terror. Kelly's son, Marine 1st Lt. Robert Kelly, was killed in November 2010 in Afghanistan.

Administration 'loves him'

In tweeting the appointment of Kelly Friday, Trump called him "a true star of my administration." 

Later, White House press secretary Sarah Huckabee Sanders issued a statement heaping praise on Kelly.

"He is respected by everyone, especially the people at the Department of Homeland Security. The entire administration loves him and no one is comparable."

Sanders said the president and Priebus "accomplished a lot together."

She said Priebus was "loyal in his dedication to the president" and added that the president "thanks him and his family for his great service to the country, and he will always be a member of the Trump Team."

But Trump had limited Priebus's power from day one, saying he and chief strategist Steve Bannon would serve as "equal partners" in implementing the president's agenda. Six months later, Trump is said to view Priebus as weak and ineffective, and he stood by as incoming communications director Anthony Scaramucci publicly impugned Priebus and in a vulgarity-laden rant called him a "paranoid schizophrenic."

Kelly has much to contend with as he attempts to do what Priebus couldn't.

Deputy Homeland Security secretary Elaine Duke will take over as acting secretary.