WASHINGTON—President Donald Trump picked cybersecurity expert Kirstjen Nielsen to be the next Homeland Security secretary, putting a low-profile figure into a critical job after former Secretary John Kelly was named White House chief of staff.
Ms. Nielsen, 45 years old, was Mr. Kelly’s chief of staff at the Department of Homeland Security. She followed him to the White House, where she serves as principal deputy chief of staff, Mr. Kelly’s top aide. Her close relationship with Mr. Kelly was critical in the decision to name her to the post, people familiar with the selection said Wednesday.
Secretaries of homeland security have traditionally been high-profile figures, including former governors and, with Mr. Kelly, a retired Marine Corps general. That isn’t the case with Ms. Nielsen. But administration officials point to her wealth of experience in many issues the agency handles and note that she would be the first secretary to have worked at the agency before.
One downside, though, is she lacks the sort of experience communicating with the public that elected officials have, and that can be important in an emergency or in the case of a terror attack. Acting Secretary Elaine Duke, another nonpolitical homeland expert, ran into trouble for indelicate comments in response to a question about one of the recent hurricanes, for instance.
But Ms. Nielsen is well steeped in the issues that the agency deals with on a daily basis, from her service during the Trump and George W. Bush administrations.
She worked at the Transportation Security Administration and for the White House Homeland Security Council during the Bush years. She then worked in the private sector—at positions including the Center for Cyber and Homeland Security at George Washington University and the National Cybersecurity Center—before being brought into the Trump transition to help guide Mr. Kelly through his Senate confirmation process.
If confirmed by the Senate, she would succeed Ms. Duke, who was deputy secretary under Mr. Kelly and has been acting secretary since July.
DHS, created in the aftermath of the 2001 terrorist attacks, is a sprawling operation with responsibilities including immigration enforcement, disaster response, the Secret Service and U.S. border and airport security.
As such, Ms. Nielsen would be thrust to the forefront of some of the administration’s most controversial initiatives. Those include Mr. Trump’s effort to build a wall on the southwest border with Mexico, increase deportations of undocumented immigrants, enforce travel restrictions on people from targeted countries, and increase vetting of travelers to the U.S. She would also take over the Federal Emergency Management Agency at a time of intense recovery efforts following a series of damaging hurricanes.