Democratic lawmakers are concerned Donald Trump will replace outgoing Homeland Security Secretary Kirstjen Nielsen with an immigration hard-liner, but the White House has yet to clearly explain what the president wants her successor to do differently.

Nielsen’s coming departure will only complicate the Senate calendar, adding another senior administration position the chamber might have to process in coming weeks or months. Senators on the relevant oversight panels will be taken away from other work — such as annual spending bills — to focus on grilling nominees.

Then, floor time will be eaten up before the Republican majority likely pushes all of them to confirmation.

Nielsen’s ouster is part of an emerging overhaul at the Department of Homeland Security. Also pushed out Monday was U.S. Secret Service Director Randolph “Tex” Alles. And late last week, the White House withdrew the nomination of Ron Vitiello to lead the Immigration and Customs Enforcement agency.

“Ron is a good man, but we’re going in a tougher direction,” Trump told reporters Friday.

[Trump’s double backtrack ‘probably won’t matter very much’]

Trump tweeted Sunday he will install Kevin McAleenan, the current U.S. Customs and Border Protection commissioner, as the acting Homeland Security secretary, once Nielsen officially leaves Wednesday. 

McAleenan will join acting secretaries at the Pentagon and Interior Department. Mick Mulvaney, the Office of Management and Budget director, is currently the acting White House chief of staff. And Russell Vought is the acting OMB boss while Mulvaney is running the West Wing. There’s also an acting U.S. ambassador at the United Nations.

Nielsen initially resigned effective Sunday after a meeting with Trump in the White House residence during which they reportedly clashed over the president’s desire to revive a policy of separating children from adults — in some cases, their parents — at the southern border. But it was later announced she would stay on the job until Wednesday.

“The president wants the problem solved and the crisis averted,” Hogan Gidley, the White House principal deputy press secretary, said during a brief interview. “He has the right and deserves to have a team in place he feels can best implement his policies.”

But Gidley and other White House officials were unable Monday to describe exactly what it was that the president wanted Nielsen’s successors to do differently. They chided reporters for focusing on the “palace intrigue” surrounding Nielsen’s departure — but they struggled to describe, even in broad terms, just what Trump wants from his next DHS chief.

‘Most difficult post’

When pressed, one White House official said there was a feeling in the West Wing that it was “just time” for Trump and Nielsen to part ways after bumping heads on numerous occasions during her 16-month tenure.

“The president wants fewer people showing up at the border,” said Cristobal Ramón, an analyst at the Bipartisan Policy Center. He predicted White House officials will seek “something more stringent and tougher to try to make it more difficult for [undocumented] migrants to access the asylum system.”

That likely means the next DHS leader would be tasked with making administrative and regulatory changes to the asylum system, Ramon said, calling such moves a “short- to medium-term approach.”

White House officials, Democratic lawmakers and legal experts agree that whatever Trump wants next is unlikely to be something Nielsen’s successor can do swiftly — especially while working for an immigration hard-liner who is growing more and more frustrated with the increased number of attempted border crossings and apprehensions there.

Gidley, the White House spokesman, acknowledged that many of the immigration changes Trump wants — like overhauling the program that grants preference to people with U.S. citizen or legal resident relatives; and the visa lottery process — would require congressional action. But there’s no effort afoot to craft the kind of bipartisan immigration overhaul bill that would be able to pass both chambers.

[Road ahead: Barr testifying on DOJ budget, likely to get grilled about Mueller report]

“[Nielsen] held one of the most difficult posts in the U.S. government at one of the most difficult times for the issues DHS faces and worked for a very difficult boss,” said Carl Tobias, a law professor at the University of Richmond. “The big takeaways from a legal perspective is that these are exceedingly difficult issues and many of them are being resolved by the federal courts, which mean there will be no quick answers.”

For McAleenan, or any permanent nominee who might eventually be confirmed by Senate, “the critical issues seem to be the border, migration issues [and] turmoil in South America,” Tobias said. “Trump’s choice seems to have much relevant experience in a number of key areas,” he added of the soon-to-be-acting DHS chief, who has had jobs focused on securing the southern border, counterterrorism and trade while with Customs and Border Protection. 

But McAleenan has spoken publicly about the need for U.S. aid dollars to countries such as Honduras, El Salvador and Guatemala — from where many recent undocumented migrants originate. That could prove a problem during his interactions with Trump, who has moved in recent days to turn off the American aid spigot to those countries over frustrations that their governments are doing too little to prevent their citizens from fleeing north.

Miller’s time

Meantime, Democratic lawmakers and aides are gravely concerned that hard-line White House policy adviser Stephen Miller, who reportedly has Trump’s ear and is leading the mini-purge, will convince the boss to nominate someone with the same ideological beliefs that are skeptical of any benefits of legal or illegal immigration from any country.

“We must address the root causes driving families from the Central American countries of Guatemala, Honduras, and El Salvador to flee for their lives in the first place,” one Senate Democratic source said.

California Sen. Kamala Harris, a member of the Homeland Security Committee and a 2020 Democratic White House hopeful, tweeted Monday that she would “under no circumstances support a nominee who does not forcefully denounce this administration’s policy of separating families at the border.”

Delaware Democrat Chris Coons said Monday that what is “striking is how many of the secretaries of the largest departments of this government are acting at this point.”

“Kirstjen Nielsen will be known for implementing a cruel policy of forcibly separating parents and children,” he told CNN. “She had a background in cyber security. I think that’s not what she’s going to be known for. And it, frankly, has to raise the question for anyone who’s offered a Cabinet opportunity [from] President Trump, whether their reputation will survive.”

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