https://www.newyorker.com/news/news-desk/why-trumps-fourth-secretary-of-homeland-security-just-resigned
Why Trump’s Fourth Secretary of Homeland Security Just Resigned
By Jonathan Blitzer
7:49 P.M.

When Kevin McAleenan became the acting Secretary of Homeland Security, in April, a D.H.S. official, who knew McAleenan personally, told me, “I’m not sure how he can finesse things with this Administration.” Donald Trump had just fired Kirstjen Nielsen, a former official in the George W. Bush Administration, despite the fact that she had championed some of the Trump Administration’s harshest immigration policies, including family separation. McAleenan, who had served in the Obama Administration, was widely regarded as a Democrat. He publicly opposed Trump’s decision, earlier that spring, to cut aid to Central America, and was taking over the Department at a moment when more than a hundred thousand migrants were being apprehended at the border in a single month. On Friday, after six months in the post, McAleenan resigned, becoming one of the shortest-serving secretaries in the department’s history. And yet, according to three people with knowledge of McAleenan’s thinking, the Secretary had somehow managed to leave the Trump Administration mostly on his own terms. The reasoning behind the decision, one of them told me, “was sixty per cent because he had achieved the mission objectives, and forty per cent because he had to avoid being branded as Trump’s border cop.” ...

Trump never exactly soured on McAleenan, but he undercut him. For one thing, the President did not formally nominate McAleenan for Senate confirmation, which eroded his standing within the Administration. D.H.S. consists of twenty-two agencies, with an annual budget of fifty billion dollars and some two hundred and forty thousand employees, spanning the Secret Service, the Federal Emergency Management Agency (FEMA), the Coast Guard, the Transportation Security Administration, and Immigration and Customs Enforcement (ICE). Its portfolio includes briefs related to domestic terrorism, cybersecurity, and disaster relief. “We always had to work extremely hard to make sure the department didn’t get turned into a political tool,” one former D.H.S. official told me last year. “We tried to run it like other departments that were above the fray, but it’ll always be a challenge because of the immigration issue.” Among many current and former D.H.S. officials, however, there was rising concern that the President’s obsessive focus on immigration enforcement was dragging the department even further into the realm of domestic politics. At one point earlier this summer, Trump bumped into McAleenan in Washington just before the secretary was due to give a speech on cybersecurity. “Why aren’t you at the border?” Trump asked him, according to someone present at the time.

In June, Trump named two partisan appointees to key posts within D.H.S.—Ken Cuccinelli, the former Virginia attorney general, to lead Citizenship and Immigration Services, and Mark Morgan, to head C.B.P.—both of whom routinely sidestepped McAleenan, their direct boss, in press conferences and appearances on Fox News. This summer, while McAleenan was negotiating an emergency funding bill on the Hill—in part, by trying to convince restive Democrats that D.H.S. would use appropriations for humanitarian, not enforcement, efforts—Cuccinelli and Morgan publicly championed a nationwide ICE operation that the President had announced, to the agency’s surprise, on Twitter. McAleenan had opposed the operation, which targeted immigrant families, but Cuccinelli and Morgan rallied to the cause. “What I don’t have control over is the tone, the message, the public face and approach of the department in an increasingly polarized time,” McAleenan later told the Washington Post. “That’s uncomfortable, as the accountable, senior figure.”

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