On Thursday, President Trump fired Kristi Noem, his secretary of homeland security, whose agency is at the center of his second-term agenda. Hamed Aleaziz, who covers the department, explains how Ms. Noem ended up losing the president’s trust. Guest: Hamed Aleaziz, who covers the Department of Homeland Security and immigration policy in the United States for The New York Times. Background reading: Bulletproof vests and Rolex watches: the rise and fall of Kristi Noem. Mr. Trump said he would replace Ms. Noem with an Oklahoma senator, Markwayne Mullin. Photo: Nicole Hester/USA Today Network, via Reuters For more information on today’s episode, visit nytimes.com/thedaily. Transcripts of each episode will be made available by the next workday. You can also subscribe via your favorite podcast app here https://www.nytimes.com/activate-access/audio?source=podcatcher. For more podcasts and narrated articles, download The New York Times app at nytimes.com/app. Hosted by Simplecast, an AdsWizz company.