Trump ousts DHS secretary Kristi Noem and replaces her with Republican senator

Donald Trump on Thursday announced he was replacing Kristi Noem as homeland security secretary, after the killing of two US citizens by immigration agents and mounting reports of her questionable personal conduct attracted bipartisan criticism.

It was the first major personnel shakeup of Trump’s second term, and in a post on Truth Social, the president said Markwayne Mullin, an Oklahoma senator, would take over from Noem starting on 31 March. The secretary, who he said “has served us well, and has had numerous and spectacular results (especially on the Border!)” would become special envoy for “the Shield of the Americas”, a security initiative Trump said he planned to launch over the weekend.

A Republican former congresswoman and governor of South Dakota, Noem was considered a potential running mate for Trump as he sought re-election in 2024, but ultimately passed over after she admitted in a memoir to killing a dog she owned. The president instead nominated her to lead the Department of Homeland Security (DHS), which oversees Immigration and Customs Enforcement (ICE), the border patrol and other agencies that took to the streets of major US cities during Trump’s second term to carry out his mass deportation agenda.

Noem became a public face of the crackdown, which ensnared immigrants with documentation and without as well as US citizens, appearing regularly on conservative television networks as well as in promotional material on DHS social media accounts.

After federal agents deployed to Minneapolis killed Renee Good and then, weeks later, Alex Pretti, Noem accused both US citizens of being involved in “domestic terrorism”. But the allegation appeared to fly in the face of what was known about both’s participation in anti-ICE protests, and Democrats along with some Republicans called for Noem to resign after Pretti’s death.

Simultaneously, reports began to emerge of Noem and Corey Lewandowski, a former Trump campaign manager who was her senior adviser, engaging in a personal relationship, despite both being married, amid turmoil at the department.

In February, the Wall Street Journal published a lengthy report into her leadership of the DHS that found Noem and Lewandowski had done little to obfuscate their personal relationship, while berating staff and administering polygraph tests to those they did not trust.

The pair had been traveling on a luxury 737 Max jet equipped with a private cabin, which the department has been seeking to acquire for around $70m for “high-profile deportations”. In one instance, Lewandowski fired a US Coast Guard pilot who left a blanket belonging to Noem on a plane, but then reinstated him because there was no one else to fly them back.

Democrats excoriated Noem when she appeared before the House and Senate judiciary committees in early March. She refused to retract her comments calling the US citizens killed in Minneapolis “domestic terrorists” while dismissing a question about whether she was having “sexual relations” with Lewandowski as “tabloid garbage”.

But even some Republicans signaled concerns with her leadership, with Louisiana senator John Kennedy questioning why the DHS gave $220m to a firm linked to Noem’s former spokesperson to produce advertisements in which the secretary was featured prominently.

Thom Tillis of North Carolina, one of the few Republicans who had called for Noem’s resignation, threatened to hold up Senate business if he did not get responses from her to a slew of questions, while accusing her of obstructing investigations by the department’s inspector general.

He also took her to task for killing both a dog and a goat, as she documented in her book, saying: “Those are bad decisions made in the heat of the moment, not unlike what happened in Minneapolis.”