Kirstjen Nielsen helped shepherd President Donald Trump's Department of Homeland Security secretary pick through his Senate confirmation process. Now she's got her own team guiding her through those same hoops.

Trump surprised many in his administration when he announced his decision to nominate Nielsen to run the sprawling agency, which has been leading the charge on implementing Trump's aggressive immigration agenda. Nielsen had served as former DHS Secretary John Kelly's top deputy early in the Trump administration, and she moved with him to the White House when he was elevated to Trump's chief of staff.

She appeared before the Senate Homeland Security Committee on Wednesday for her confirmation hearing and said cybersecurity would be one of her top priorities.

It's been a lightning-fast rise for the 45-year-old, who arrived in Trumpworld only after Trump won the election and who joined his transition team, on the recommendation of several former co-workers, to help guide Kelly through the confirmation process. Nielsen quickly earned the retired general's trust, impressing him with her work ethic and command of the issues and standing out in a team filled with political appointees.

Nielsen's supporters describe her as a straight shooter, with a relentless work ethic and high standards.

"Among an incredibly overburdened and hardworking staff, Kirstjen stood out in the sense that she was indefatigable. She would work long hours, she would never complain, she would stay until it got done," said Frances Townsend, Nielsen's boss in President George W. Bush's administration, where she served as special assistant to the president and senior director for prevention, preparedness and response on the White House Homeland Security Council.

"It was extraordinary," Townsend said.

Townsend said Nielsen was always the first to arrive in the morning and the last person to leave at night, and she expected those around her to work as hard as she did.

Townsend recalled how men would leave their suit jackets on the backs of their chair in the evening so it would appear as though they'd gone to the restroom instead of home. One woman, she said, would stash her purse in the women's restroom so she could sneak out on the sly.

"She didn't want to have her purse on her shoulder," said Townsend of the Nielsen underling. "As her boss, I absolutely loved her."

It was one of several such stories. Two transition officials recalled how, during the lead-up to Kelly's confirmation hearings, Nielsen became ill from working too hard and wound up coughing and displacing a rib while suffering from a bronchial cold. Instead of taking time off, however, she was back to work the next day.

"No job is too small — or, should I say, no job is too big," said Blain Rethmeier, who first worked with Nielsen in the Bush White House and is now working on her "sherpa" team.

But those same qualities have also chafed some colleagues, both at DHS and the White House, who have been put off by her brusque, no-nonsense style.

As she worked with Kelly to impose order in a chaotic and dysfunctional White House that lacked clear lines of command, people inside and outside the White House complained she was controlling access to Kelly, alienating staffers and failing to return phone calls. A constant presence in Kelly's orbit, Nielsen quickly established herself as the West Wing "enforcer."

Similar concerns extended to the DHS, where current and former staffers recall her canceling other people's meetings with Kelly if she couldn't attend.

For some at the DHS, it was a shock that a person so polarizing and with minimal management experience had been nominated to run a department of 240,000 people that oversees the Federal Emergency Management Agency, immigration policy and the Transportation Security Administration, among other major divisions. When acting DHS Secretary Elaine Duke announced the news to senior department leadership in a hastily arranged conference call, she was met with what one person on the line described as dead silence.

The person, like others, spoke to The Associated Press on condition of anonymity for fear of angering Nielsen and compromising their jobs.

Her supporters, however, have pushed back at that characterization, dismissing it as jealousy and, perhaps, sexism.

"The people who complain, are, in my opinion, people who don't work as hard," Townsend said. Nielsen declined an interview request.

Nielsen has experience on the Hill and created and managed the Offices of Legislative Policy and Government Affairs at the TSA. After serving in the Bush administration, she worked as general counsel and a president at the Civitas Group consulting firm before founding her own private consulting firm, Sunesis Consulting, where she advised senior domestic and foreign government officials and senior private sector officials on cyber and preparedness issues. (She is also an avid surfer who played Division I soccer in college.)

If confirmed by the Senate, Nielsen will be the first DHS secretary to have previously worked for the department, excluding acting secretaries.

She'll also be the first with a cybersecurity background. Frank Cilluffo, a former director of the president's Homeland Security Advisory Council in the Bush administration, said that when it comes to the department, "she knows it inside and out."

Nielsen, he said, would be able to "parachute in" and speak to various analysts and teams in "the same language that they speak and understand the issues."

She's an "incredibly thoughtful" analyst, he said. "I actually think she's a wonk at heart."


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