U.S. President Donald Trump announced Thursday that Markwayne Mullin will take over as secretary of the U.S. Department of Homeland Security, replacing Kristi Noem in a major leadership change tied to the administration’s immigration policies.
"I am pleased to announce that the Highly Respected United States Senator from the Great State of Oklahoma, Markwayne Mullin, will become the United States Secretary of Homeland Security (DHS), effective March 31, 2026," Trump wrote on Truth Social.
Noem will serve as "Special envoy for The Shield of the Americas," Trump said.
Noem, a former governor of South Dakota, became one of Trump's most high-profile Cabinet secretaries with social media posts that portrayed immigrants in harsh terms, highlighting cases of alleged criminal offenders and using vitriolic language. She faced criticism in January when she quickly labeled two U.S. citizens fatally shot by federal immigration agents in Minneapolis as committing "domestic terrorism."
Videos that emerged after the deaths undercut the assertion by Noem and other Trump officials that the two deceased - Renee Good and Alex Pretti - were violent aggressors. The public backlash for deaths led the Trump administration to move to a more targeted approach to immigration enforcement in Minnesota after months of sweeps through U.S. cities that led to violent clashes with residents opposing the crackdown. Democrats in the U.S. House of Representatives moved to impeach Noem and at least two Republicans in Congress called for her to lose her job after the incidents.
During congressional hearings in March, Democrats and some Republicans criticized Noem for her approach to the immigration crackdown and management of DHS, including concern over a $220 million ad campaign that heavily featured Noem. The staffing change raises questions about whether the Trump administration could seek to intensify its mass deportation push or retreat to a more targeted approach.
Under Noem's leadership, masked immigration agents surged into Los Angeles, Chicago and Washington, D.C., scouring neighborhoods and Home Depot parking lots in search of possible immigration offenders. The popularity of Trump's immigration approach fell as agents detained U.S. citizens and tear-gassed streets in an attempt to drive up deportations, which last year fell short of the administration's goal of 1 million per year.
While Noem, 54, served as a prominent proponent of Trump's agenda, White House Deputy Chief of Staff Stephen Miller, a long-time Trump aide, controls Trump's immigration policy. Noem was quickly confirmed to lead the 260,000-employee Department of Homeland Security in January 2025 after Trump took office.
On social media, she referred to immigrants convicted of crimes as "scumbags" even as the number of non-criminals arrested by immigration authorities rose under Trump. She joined immigration enforcement operations on the ground in New York City and visited a maximum-security prison in El Salvador where Venezuelan immigrants deported by the Trump administration were being held without charges or access to lawyers.
The number of migrants caught trying to illegally cross the U.S.-Mexico border plummeted under Trump's restrictive policies, a steep drop after high levels of illegal immigration under former President Joe Biden, a Democrat.
Noem, reflecting Trump's agenda, also took steps to cut legal immigration programs and increase vetting. She ended several Temporary Protected Status programs that provided work permits to hundreds of thousands of immigrants from Venezuela, Haiti and other nations, drawing legal challenges.
After an Afghan immigrant was accused of attacking National Guard members in Washington, D.C., Noem said she recommended that Trump place "a full travel ban on every damn country that’s been flooding our nation with killers, leeches, and entitlement junkies."
Critics said Noem demonized immigrants and promoted an immigration enforcement strategy that targeted non-criminal, working immigrants and families. During Noem's tenure, the number of deaths in immigration detention rose to a two-decade high while staff in DHS oversight offices were slashed sharply.
