President Donald Trump is ending a program that allowed many unauthorized immigrants to work and live in the US — the most aggressive move of his immigration crackdown so far, and a decision that will ultimately put nearly 800,000 immigrants who came to the US as children or young teenagers at risk of deportation.

Attorney General Jeff Sessions announced Tuesday that the government will stop granting protections from deportation under the Deferred Action for Childhood Arrivals program, instituted by President Barack Obama in 2012.

According to an official Department of Homeland Security memo, people who have already applied for DACA protection will have their applications processed normally, but the government won’t accept any new applications after Tuesday.

Those currently covered under the program — which grants protections for two years — will be able to retain their protections and work permits until they expire.

If their DACA protections are set to expire before March 5, they will have a month — until October 5 — to apply for one last renewal. And those who are set to lose their protections on March 6 or later will simply fall back into unauthorized status.

The catch: All of this will happen only if Congress fails to pass a bill in the next six months that protects DACA recipients, either by continuing to offer them temporary protection or granting them a path to legalization.

Trump’s decision is an attempt to shift pressure from the White House (after several months of back and forth within the Trump administration about the fate of a program associated with Obama, and which its critics see as an unconstitutional amnesty) and onto Congress to find a way to keep DACA recipients living safely and working in the US.

But after Congress’s failure to repeal and replace the Affordable Care Act earlier this year, it’s not clear whether Congress will be able to get its act together to pass an immigration bill — or what a bill that could satisfy both 60 senators and the president would look like.

In the meantime, the Trump administration is acting as if Congress won’t pass a bill — slowly winding down DACA now, in anticipation of sunsetting the program entirely starting on March 5. It isn’t punting on DACA; it’s preparing to end it, albeit gradually.

Tuesday marks the beginning of the end for the DACA era: a half-decade period during which a generation of young immigrants, now predominantly in their 20s and 30s, were able to put down roots and advance careers in the US without the constant threat of deportation.

It marks the beginning of six months of existential anxiety, as hundreds of thousands of immigrants struggle to go on with their lives without knowing whether they’ll be accepted as inhabitants of the United States by April — or whether the only certainty they’ll get at the end of six months is knowing the date on which they’ll lose their ability to work in the US legally and gain the constant threat of deportation.

Beyond the risk of deportation, immigrants currently protected by DACA now face the loss of their ability to work legally in the US; of their driver’s licenses in many states; and of the assurance that they are fundamentally wanted in the country where they grew up.

For the next six months, DACA recipients will live under crushing uncertainty. After that time, if Congress doesn’t pass a bill, DACA recipients — one by one — will face an impossible choice.

They can resign themselves to the lives they lived five years ago. They can try to retain the gains they made over the past five years, even without the protections that made it possible. Or they can try to find a more welcoming place in which to live.

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DACA transformed hundreds of thousands of lives

The question of what to do with unauthorized immigrants who’d come to the US as children has been a subject of political debate for the past 16 years — ever since the first version of the DREAM Act (which would allow those immigrants to apply for legal status and eventually allow them to seek US citizenship) was introduced in 2001.

But the DREAM Act never passed Congress. In the most recent attempt, in December 2010, the bill failed to clear the 60-vote threshold needed to break a filibuster. Meanwhile, although the Obama administration said it was changing the way immigration enforcement operated, agents continued to arrest and deport some “low-priority” immigrants — including those who would have qualified for the DREAM Act.

DACA, announced by President Obama in June 2012 and rolled out that August, was a solution to that policy problem: It allowed immigrants to apply for protection proactively; if granted protection, they were allowed to work legally in the US.

It was always temporary. The executive branch can’t create new ways for immigrants to get legal status in the US, it can just temporarily “defer” their deportation and allow them to work legally.

But for DREAMers, the ability to work legally and live without deportation threat — even for just a couple of years at a time — was appealing enough that nearly 800,000 immigrants, over half of those estimated to qualify, ultimately sought protection under the program.

And for those immigrants, for five years, their lives changed.

Research on the effects of DACA consistently shows that it’s opened up educational and economic opportunities. The most recent survey, conducted in early August 2017 by UC San Diego professor Tom Wong, under the auspices of the liberal think tank the Center for American Progress, found that annual earnings had increased 80 percent under DACA — from an average of $20,000 to an average of $36,000. (This includes immigrants who are working part time, or who are working while enrolled in school, as well as those with full-time jobs.) Sixty-five percent had bought their first car; 16 percent had become homeowners.

Five percent of DACA recipients had started their own businesses. Sixty percent of DACA recipients above the age of 25 — in other words, those most likely to have been in the workforce before DACA was rolled out in 2012 — said that with DACA they’d been able to find jobs that better suited the education and training they already had; 61 percent said they’d been able to find jobs that suited the careers they wanted to have.

These changes can’t be totally explained by the simple fact that good jobs aren’t often available to people without legal work papers.

The truth of DACA is that despite the stereotype of the high-achieving, highly educated DREAMer, many unauthorized immigrants growing up in the US didn’t achieve their academic or professional potential simply because they couldn’t see what good it would do them to succeed. As DREAMers hit their mid- to late teens, and their peers started to be able to do things they couldn’t — get driver’s licenses, apply for financial aid — many of them “transitioned to illegality,” suffering mental-health crises and often losing a desire to achieve in school because they realized the country they thought of as their own didn’t actually have opportunities for them.

There’s evidence that DACA prevented those crises. Immigrants protected by it felt American, welcomed, normal. Their mental health was better than the mental health of immigrants who didn’t qualify for DACA. They were able to help their parents and families. They were able to put down roots.

And starting on March 6 — unless Congress disrupts the Trump administration’s current plans — those roots are going to be, immigrant by immigrant, tugged at and torn up.

Trump’s attempting to use Congress to avoid responsibility either for ending DACA or protecting it in court

DACA wasn’t originally a hot-button wedge issue. The Obama administration took up the idea of a “deferred action” program under sustained pressure from immigrant-rights organizations, often led by DREAMers themselves; it announced DACA in hopes of mobilizing Latino voters in the 2012 presidential election.

It protected a population that members of the public across the political spectrum found “deserving” — and that few politicians were willing to say they wanted to see deported.

But it was President Obama’s attempt to expand deferred action to the parents of American citizens in 2014, eventually thwarted by the courts, that put the existing DACA program in the crosshairs. At the same time, immigration reformers in the Republican Party were losing power. The party’s immigration hawks were gaining strength, and Donald Trump was rising to the top of the presidential primary on a hardline immigration platform.

Trump promised in the first 100 days of his presidency to revoke all of Obama’s unconstitutional executive actions — which was widely assumed to include DACA. Immediately after the election, DACA recipients understood that they could be at risk as soon as January 20.

But Trump appeared to develop a belated understanding of just how emotionally and politically touchy a subject it was to revoke protections for people who grew up in the US. He praised the DREAMers to Time magazine in December, and acknowledged that the problem was “very tough.” He assured the public that he had a “big heart” and would come up with a solution that would have “a lot of heart.”

Ultimately, though, no compromise was forthcoming — Trump ended the program in exactly the way an executive order drafted, but not signed, in January would have done.

The timing of the decision was likely provoked by a threat from a group of Republican state officials, led by Texas Attorney General Ken Paxton, to sue the federal government if it didn’t end DACA before September 5. Several powerful Trump policy advisers — including Attorney General Jeff Sessions, who would have to defend DACA in court in the event of a lawsuit — have pushed for an end to DACA, as well.

Trump’s decision to announce an end to DACA now, but delay its implementation for six months, is something of an attempt to have his cake and eat it too: The White House appears to hope that the states will back down from their threat to sue (though it’s not clear that the states will comply), while trying to avoid the president getting blamed for targeting a politically popular group of immigrants.

Several bills that would offer some protection to DACA recipients have already been introduced in Congress, and many Republicans — including many Democrats, as well as Republicans who’ve long defended DREAMers like Sen. Lindsey Graham (R-SC) and vulnerable Republicans in swing districts — have joined Democrats in calling for Congress to pass one of them before DACA ends.

But Congress’s agenda is already extremely tight for the next six months — with a key government-funding deadline to meet at the end of the month, one last potential chance to repeal Obamacare, and a desire to pass tax reform.

Furthermore, it’s not clear what conservatives (including the president) would demand in exchange for protecting DACA recipients in a bill. In August, the administration floated the idea of a “grand bargain” that would legalize DACA recipients in return for a conservative wish list on immigration enforcement and future restrictions on legal immigration. That idea appears to have little support among Democrats or pro-DACA Republicans. But if there aren’t enough pro-DACA Republicans to pass a bill without enforcement “tradeoffs,” it might be hard to find something Democrats will be willing to give up.

If Congress succeeds, DACA recipients could end up able to get full legal status in the US — more than DACA provided them. If Congress fails, the White House will try to blame them for not having acted — while Congress will be able to blame the White House for actually ending the program.

To DACA recipients themselves, though, the distinction won’t matter.

A “delay” isn’t much comfort to immigrants themselves

In practice, the end of DACA will be immediate for many people: Anyone who hasn’t yet applied for DACA protections, either because they aren’t yet 15 years old or because they haven’t managed to pull together the $495 application fee, will be barred from the program.

Anyone whose DACA protections are set to expire before March 5, but isn’t able to pull their application for renewal together in the next month — as many as two months before they’ve been planning to renew — will lose protections even before the official March 5 “end date.”

And the government will stop processing any requests from DACA recipients to leave the country (what’s called “advance parole”) immediately. People who already have advance parole can keep it, but any applications still pending will be denied.

In other words, what the Trump administration is doing isn’t punting on DACA for six months. It’s slowly winding down DACA, in anticipation of ending it entirely. It’s saying that Congress should act, but acting as if it won’t.

That’s a commitment that DACA recipients themselves have every reason to take seriously. They’ve been living under the threat of DACA revocation since Trump’s election in November. They’ve seen Trump’s administration attempt to deport a few DACA recipients who were supposed to be protected. And now, they have a deadline over which they have no control — but which will determine the course of the rest of their lives.

What it will mean to lose DACA varies from immigrant to immigrant. Immigrants working full-time jobs will have to leave them to comply with the law, or continue working at legal risk to themselves and their employers. Immigrants in school will be able to remain enrolled, in nearly all cases, but some might have trouble retaining their financial aid for the rest of their educations (in addition to not knowing what jobs they could get in the US with the degrees they’re working to obtain).

And then there’s the threat of deportation.

Because DACA recipients gave extensive personal information to the government when they applied, many of them could easily be tracked down, arrested, and placed in deportation proceedings if the Trump administration chose to do so. Under Obama, DACA information was protected from Immigration and Customs Enforcement agents by privacy regulations, but an executive order signed by President Trump in January relaxed those restrictions.

In theory, Trump administration officials claim they’re going after immigrants with criminal records. In practice, it appears they’re going after the lowest-hanging fruit — the immigrants they can most easily track down and pick up. If that’s true, it puts DREAMers at substantial risk.

There are too many DACA recipients for the administration to arrest all of them, much less deport them — and because DACA recipients haven’t been previously deported or ordered deported, it won’t be possible to deport them now without putting them through a yearslong immigration court process. But the risk of deportation is, if anything, higher after DACA than it was beforehand.

DACA recipients have months to prepare for that possibility. But many of them —especially those who are employed full time — have no good options.

They can attempt to continue to live the lives they’re living right now, under DACA: working, driving around, being “undocumented and unafraid.” If they do that, they’re putting themselves in legal jeopardy multiple times a day, and increasing the risk of their deportation.

They can try to make plans to leave the country once their DACA grants expire: selling the car or house they purchased while protected by DACA, trying to find a country that will welcome the skills they no longer have the opportunity to use in the US. But for a cohort of people who grew up in the US, and who have spent the past half-decade living here with some legitimacy, that’s not an easy step to take — if it were, more of them would have taken it rather than live under the uncertainty of DACA to begin with.

Or they can try to return to the shadows — taking the sort of jobs they had before DACA. They can try to transition back to illegality. Whether they can do so without losing the sense of pride and accomplishment, or the sense that they were welcome in America, that DACA gave them isn’t something anyone can predict — or that anyone but them can ensure.