Kristi Noem, a two-term governor and former U.S. congresswoman, was chosen by the president-elect to lead the department responsible for key immigration and border-related actions that will be central to his plans for mass deportations and tightened access at the border.

The immigration and border-related agencies Noem would oversee include U.S. Customs and Border Protection, Immigration and Customs Enforcement and Citizenship and Immigration Services. Beyond those agencies, the department is also responsible for securing airline transportation, protecting high-profile dignitaries, responding to natural disasters and more.

She would replace outgoing DHS Secretary Alejandro Mayorkas, who was so vilified by Republicans angry at the number of migrants crossing the country’s southern border that they impeached him in early 2024.

Noem would be entering a job that was a pressure cooker under the first Trump administration. Six people cycled through the homeland security secretary position during his four years in office.