President Donald Trump suddenly withdrew the nomination of his acting head of Immigration and Customs Enforcement, Ron Vitiello, to formally lead the agency late Thursday night — in a move that appears to have shocked the Department of Homeland Security, the Cabinet department in which ICE is located.

Trump told reporters Friday morning that he’d withdrawn Vitiello’s nomination because “we’re going in a tougher direction.” It is not at all clear what he means.

The move was so unexpected that one DHS official initially told the Associated Press that the notification sent to Congress Thursday night, signed by Trump and informing them that he was withdrawing Vitiello’s nomination, must have been a “paperwork error.”

Other officials seemed unpleasantly surprised by the development. Nick Miroff of the Washington Post tweeted Friday morning that DHS sources were “baffled.”

Vitiello was also dropped from Trump’s Friday trip to Calexico, California, where he’s expected to tour the section of border barriers that his administration has anointed the first section of the Trump wall. But Vitiello is staying on as acting ICE director, presumably until a replacement is nominated and confirmed by the US Senate.

Trump hasn’t yet had an ICE director confirmed by the Senate during his two-plus years in office. His first acting director, Tom Homan, was nominated but never got a floor vote. Vitiello became acting director of the agency in June 2018 and was formally nominated in August.

The Senate Homeland Security Committee had approved Vitiello’s nomination in November — despite opposition from some chapters of the ICE union, which pointed to tweets from Vitiello criticizing Trump before the 2016 presidential election. The Senate Judiciary Committee (which also needed to approve the nomination before the full Senate could vote) was set to vote on Thursday, but committee chair and Trump confidant Sen. Lindsey Graham (R-SC) delayed the vote before the hearing for unspecified reasons.

There’s no particularly obvious “tougher direction” for ICE to go right now

Trump’s characterization of the withdrawal as a policy move — going in a “tougher direction” — makes it especially weird that the other people currently implementing immigration policy knew nothing about it in advance. It reflects either Trump’s ongoing ignorance of what his administration is actually doing on immigration or his desire, born out of frustration, to take the reins away from DHS and start calling the shots himself.

Either way, it’s not obvious what a “tougher direction” for ICE would be.

Trump is in the midst of another temper tantrum about current US immigration policy. But his attention has generally been fixed on the genuinely unprecedented influx of Central American families at the US-Mexico border. And ICE is in charge of immigration enforcement in the interior of the US, not at the border.

Trump’s recent complaints about immigration, to the extent that they bear any relationship to reality, have been about the failure of Mexico and Central American countries to stop northward migration to the US; about the asylum laws that require that anyone who can show a “credible fear” of persecution to be allowed to stay in the US and apply for asylum; and about an unspecified but now repeated lament that “we have to get rid of judges.” (No one else in the administration has said this; other figures in the Trump administration have made it clear that the need is for more judges to hear cases more quickly, and for fewer asylum seekers to go in front of judges at all.)

None of that has anything to do with ICE. ICE’s primary responsibilities are arresting immigrants within the US, detaining immigrants pending deportation hearings, prosecuting immigrants in those hearings, and deporting those who are ordered deported.

ICE has been more aggressive on all these fronts under the Trump administration than it was in the last years of the Obama administration, and is setting new records for the number of immigrants in detention (blowing through its budget to do so). Just this week, it launched the biggest workplace raid in a decade, arresting more than 280 immigrants at a Texas cellphone repair facility. But it’s still not arresting or deporting as many immigrants as it did in Obama’s first term.

This is partly due to the decreased willingness of blue cities and states to defer to ICE in picking up immigrants from jail after they’d otherwise be released, and partly — especially in the past year — because resources are being taken up dealing with the influx of families and asylum seekers at the border.

The Trump administration has put a lot of emphasis on rolling out aggressive policies that make more people vulnerable to deportation. But that doesn’t automatically get people deported. ICE actually has to arrest them and open (or reopen) cases against them to do that.

ICE’s detention responsibilities extend to detaining anyone caught at the border within 72 hours of their apprehension. But they’re constrained, much to the Trump administration’s frustration, by a court ruling that limits the time families can be detained before they must be released into the US pending the resolution of their court cases.

There have been questions about coordination between ICE and Customs and Border Protection (the agency overseeing border enforcement) when it comes to the transfer of migrant families. But Trump’s comments about being “tougher” don’t necessarily reflect that.

It’s also doubtful that whoever Trump might nominate in lieu of Vitiello would be confirmed by the Senate. Democrats are increasingly unwilling to endorse any aspect of federal immigration enforcement as run by Trump, and some Republicans remain leery of Trump immigration-hawk favorites like former Kansas Secretary of State Kris Kobach.

When Vitiello was nominated, he was seen as the only confirmable candidate for the position; he was a career law enforcement officer who’d come from a leadership position at CBP. That, apparently, is no longer tough enough for Trump. Who could pass that bar, whether the Senate will fall in line, and what a “tougher direction” might look like in practice remain to be seen.