Homeland Security Secretary Kirstjen Nielsen resigned on Sunday amid the administration's growing frustration and bitterness over the number of Central American families crossing the southern border, two people familiar with the decision said. President Donald Trump thanked her for her work in a tweet and announced US Customs and Border Protection Commissioner Kevin McAleenan would be taking over as acting head of the department, the AP reports. McAleenan is a longtime border official who is well-respected by members of Congress and within the administration. The decision to name an immigration officer to the post reflects Trump's priority for a sprawling department founded to combat terrorism following the Sept. 11 attacks.
Though Trump aides were eyeing a staff shake-up at Homeland Security and had already withdrawn the nomination for another key immigration post, the development Sunday was unexpected. Nielsen traveled to the US-Mexico border on Friday with Trump to participate in a roundtable with border officers and local law enforcement. But privately, she had grown increasingly frustrated by what she saw as a lack of support from other departments and increased meddling by Trump aides, the people said. She apparently went into a meeting with Trump at the White House in Sunday not knowing whether she'd be fired or would resign, and she ended up resigning. Her resignation letter (see it at CNN) had not a whiff of controversy, unlike others who have left from the administration.
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