McAleenan had been frustrated with a cadre of Trump’s appointments to senior immigration roles and recently told The Washington Post that he was struggling to control his department. More hard-line figures have attacked him as insufficiently committed to the president’s immigration agenda, while critics of those policies argue he has used conciliatory rhetoric to lend cover to harsh measures.
Trump in turn had questioned whether McAleenan was loyal to him.
A person close to McAleenan said he resigned Friday after weeks of growing disenchantment with his standing in the administration. He was never formally nominated for the job.
“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 said in an interview with The Washington Post. “That’s uncomfortable, as the accountable, senior figure.”
His tenure at DHS was marked by the implementation of several contentious border policies that have significantly tightened access to the U.S. asylum system — policies he has defended as necessary to “restore integrity” to a U.S. immigration system swamped with a backlog of nearly 1 million pending cases.
McAleenan has been more isolated in recent weeks after the departure of several top aides and close allies in recent months. In addition, his relationships have been strained with other senior figures, especially Mark Morgan, the acting commissioner of Customs and Border Protection, and Ken Cuccinelli, the acting director of U.S. Citizenship and Immigration Services.
McAleenan’s exit leaves the bare-bones leadership structure at DHS even thinner. Every major immigration agency is run by leaders in acting roles.
DHS was created after the Sept. 11 terrorist attacks, and previous presidents have placed a high priority on having a Senate-confirmed leader running the department, which has 240,000 employees and a $50 billion annual budget.
Trump, who has said he prefers leaving top officials in “acting” roles in order to make it easier to remove them, left McAleenan in the job without a nomination for six months, longer than any other previous DHS chief.
DHS’s acting deputy secretary, David Pekoske, is next in line to succeed McAleenan. Pekoske, who is also the top official at the Transportation Security Administration, is the only other senior DHS leader who has been confirmed by the Senate.
Unlike McAleenan, Pekoske does not have a background in immigration enforcement, and he has told others he would like to return to his job running TSA full time.
McAleenan’s departure opens the possibility the president will seek to install a more hard-line figure at the top of DHS for his reelection campaign. In his tweet Friday, Trump said he would name a new acting secretary next week.
Trump installed McAleenan, 48, at the head of DHS after removing then-secretary Kirstjen Nielsen, saying he wanted someone “tougher” in the role, and told aides that McAleenan had the look he was going for, with the trim, stern demeanor of a federal agent.
Trump was willing to look past the warnings of border hawks who told him McAleenan was an “Obama guy” raised in California who had a record of donating to Democrats.
Trump said in July that he was preparing to place former ICE director Tom Homan in the role of a White House “border czar.” Homan did not accept the position, but several administration officials have speculated that the president will establish such a role at the White House to coordinate among federal agencies responsible for immigration and border enforcement.
Asked last month why Trump had not nominated McAleenan for the DHS job despite praising his performance, White House officials declined to comment.
“Secretary McAleenan is doing a fantastic job implementing the president’s plan to secure the southern border, build the wall, halt illegal immigration and stop the dangerous practice of catch-and-release,” said Hogan Gidley, the deputy White House press secretary, in a statement to The Washington Post at the time.
His departure opens a place for the president to install a more hard-line figure at the top of department, something supporters have urged.
McAleenan’s exit ends a nearly 20-year career in federal law enforcement. He was recruited to join CBP after the Sept. 11 terrorist attacks, creating and running the agency’s anti-terrorism office. At 35, he was port director in charge of security for Los Angeles International Airport and 17 other airports in southern California.
He was confirmed as CBP commissioner in March 2018 by a 77-19 vote, a margin reflected his standing among Democrats as a moderate and a career official.