Millions of unauthorized immigrants and their families are dreading the day President Donald Trump takes office.

As a candidate, Trump made clear over and over again that anyone in the US without papers should be at risk of deportation at any time. That includes the 740,000 or so young adults protected by President Obama’s Deferred Action for Childhood Arrivals (DACA) program, as well as millions of other long-resident immigrants without criminal records who weren’t formally protected but who weren’t deportation priorities for the Obama administration, either.

Speaker of the House Paul Ryan made an effort to reassure those immigrants Thursday night, during a televised CNN town hall.

A DACA recipient asked Ryan whether she’d be deported; Ryan told her she’d be safe. “If you're worried about, you know, some deportation force coming, knocking on your door this year, don't worry about that,” he said.

He shouldn’t have said that. Paul Ryan and Congress can’t pick who gets deported and who doesn’t — and Donald Trump, once inaugurated, will have all the forces he needs to deport an immigrant like her.

Paul Ryan to woman protected under DACA: Don't worry about a deportation force knocking on your door #RyanTownHall https://t.co/ufmQPAIEvP — CNN (@CNN) January 13, 2017

The government already has the “deportation force” Trump needs

Ryan fixated on the idea of a “deportation force” that would be mustered to round up immigrants — an idea that was floated by Trump early in his campaign.

If Trump wanted to do something like that, Congress would be able to stop him: It could refuse to appropriate the billions of dollars he’d need. But the federal government, as it exists right now and as Trump will inherit it in a week, doesn’t need a new budget line for a “deportation force” to deport immigrants. It already has thousands of Immigration and Customs Enforcement agents tasked with tracking down unauthorized immigrants living in the US and deporting them.

Right now the US has the capacity to deport about 400,000 immigrants a year — the question is which ones. And that’s not something Congress can control. How ICE uses its resources to catch and deport immigrants is a matter of executive branch policy.

If immigrants are caught and deported at random, the chance that any given unauthorized immigrant will be caught and deported at any given time isn’t sky-high, but it isn’t zero, either. Living under the threat of deportation is a trauma that unauthorized immigrants have been struggling with for years.

President Obama’s policies, especially during his second term, tried to reduce that threat by reassuring certain groups of immigrants that they wouldn’t be at risk of deportation. But Trump made it clear during the campaign that to him, that approach defeats the purpose of having immigration laws to begin with — and the ICE agents in the field who’d be carrying out his policy, and who endorsed his run for the presidency, would seemingly agree.

The day Trump arrives in office, without asking Paul Ryan’s Congress to spend a dime, he’ll have the capacity to restart many of the aggressive immigration enforcement tactics of the Bush administration, with the 400,000-deportation-a-year efficiency of the Obama administration. In particular, President-elect Trump could make it much easier for local law enforcement to scoop up unauthorized immigrants for minor offenses or immigration violations — which could turn any unauthorized immigrant in the US, including the woman who confronted Ryan, into one of the “illegal immigrant criminals” Trump says he wants to deport first.

If Trump gets rid of the DACA protections (something he will have the power to do as soon as he arrives in office, but which he’s been oddly silent about since the election), the woman who confronted Ryan will be under threat of deportation. She may not have an ICE agent knocking on her door on January 21 or 22. But any time she, say, drives a car, she’ll be at risk of getting pulled over and subsequently deported.

The only thing Congress could do to prevent that would be to pass a bill granting legal presence to unauthorized immigrants. Some members of Congress (including the few remaining Republicans, like Sen. Lindsey Graham, who continue to support comprehensive immigration reform) are pushing for a bill called the BRIDGE Act, which would basically extend DACA for a few years if Trump tries to kill the program.

If Ryan’s reassurance during the CNN town hall was a promise to support the BRIDGE Act, that would be newsworthy — but he didn’t mention it and hasn’t endorsed it. Short of doing that, though, he can’t offer his protection to immigrants looking anxiously toward the Trump administration and its deportation machine. Ryan’s performance of concern for DACA recipients is just a distraction from what the executive branch can do without him.