Kirstjen Nielsen

1972 – 20??

Kirstjen Michele Nielsen is an American attorney who served as the sixth U.S. Secretary of Homeland Security from December 2017 to April 2019 in the first Trump administration. She presided over the implementation of the family-separation "zero tolerance" policy on the southern border that ultimately separated more than 5,000 migrant children from their parents, including babies and toddlers. She publicly insisted before Congress and on social media that no such policy existed even as the administration was actively defending it in court, before being forced out by the president for being insufficiently aggressive on immigration enforcement.

Last checked: May 10, 2026, 1:06 PM