Nielsen takes the blame for the failures of Trump and Congress.

Homeland Security Secretary Kirstjen Nielsen informed President Trump on Sunday that she would be resigning in the wake of his administration’s sudden decision to drop the nomination of the leading candidate to head the U.S. Immigration and Customs Enforcement. Mr. Trump announced the resignation via Twitter later Sunday, thanking Ms. Nielsen for her service. He named U.S. Customs and Border Protection Commissioner Kevin McAleenan as Acting Secretary of Homeland Security. Ms. Nielsen, who joined the president on his trip to the U.S. border with Mexico on Friday, met with the president and his acting chief of staff Mick Mulvaney at the White House on Sunday, according to two people briefed on the discussion.

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