The Trump administration is finally playing ball on immigration.

On Wednesday, it announced it would release a “framework” for a bill it hoped to see pass Congress. On Thursday, details of that framework leaked to several news outlets, including NBC and the Daily Beast.

Those reports say that the administration is willing to allow 1.8 million unauthorized immigrants who came to the country as children to become legal residents and ultimately apply for US citizenship — including the 690,000 beneficiaries of the Deferred Action for Childhood Arrivals (DACA) program, as well as others who would have been eligible for DACA but did not apply — in exchange for a $25 billion fund for its wall on the US/Mexico border; reallocating slots currently given to immigrants via the diversity visa lottery on the basis of “merit”; and preventing people from sponsoring their parents, adult children, or siblings to immigrate to the US.

Such a framework is exactly what members of both parties in Congress — especially Republicans — have been asking for. As Sen. John Kennedy (R-LA) said on Tuesday: “At some point, we’re going to need to know exactly what the White House is thinking, because who wants to pass a bill only to have it vetoed?”

But the question now is whether the White House will stick to its framework — and whether it can get it to pass.

With little room to maneuver on policy (for a bill to pass, it will have to be liberal enough to attract 60 votes in the Senate and conservative enough to satisfy a majority of House Republicans) and very little time to debate the issue, a Trump-endorsed framework could be a game changer.

Or it could put a stake through the heart of any hopes for an immigration deal by March 5, the date on which, as it currently stands, 1,100 or so immigrants will start losing their DACA protections each day.

Which path it takes is as unpredictable as President Trump himself.

Trump’s framework might thread the needle of a bipartisan agreement — or it might not

The four issues addressed in the framework as reported — the wall, DACA, “chain migration,” and the diversity visa lottery — are clearly Trump’s own priorities. They’re the ones he’s been tweeting about for weeks. But it’s been very hard to get agreement on them between bipartisan reformers and conservatives, with the White House (and, sometimes, Trump himself) squarely in the latter camp.

And while Thursday’s call may have indicated what the White House finds acceptable, it’s not clear that it will get a majority of House Republicans, and 60 Senators, to agree.

Border security and “closing legal loopholes.” Democrats have been willing to spend money on border infrastructure as part of a DACA deal, though neither Democrats nor Republicans are eager to spend tens of billions of dollars on a “wall.” So it’s not clear how either party will welcome the White House’s $25 billion proposal.

But the question on border security isn’t just how much money is spent, and whether what’s built with that money is something that can be called a “wall” or not.

Trump’s Department of Homeland Security, as well as influential Republicans like Senate Majority Whip John Cornyn (R-TX), have stressed that border security also needs to include statutory changes that would make it harder for people to pursue asylum cases after entering the US and reduce special protections for families and unaccompanied children crossing the border. Because children and families from Central America make up an increasing share of border apprehensions, they see deterring those immigrants as an important security measure.

The talking points distributed by the White House about its plan, and obtained by Axios, hint that the framework would make changes in this regard. It mentions “same treatment of illegal aliens, regardless of country of origin” — an allusion to changing the law that prevents Border Patrol agents from summarily deporting unaccompanied children from countries other than Mexico. And it refers to changing “the ‘catch and release’ policy through which immigrants are released while awaiting a hearing” — which would make it harder for asylum seekers to get a lawyer while their cases are pending.

Democrats have rejected past attempts at these changes as cruel: a crackdown on people fleeing gang violence that doesn’t make anyone safer. It’s not clear how many of them will accept these changes now as the cost of citizenship for DREAMers.

Preventing people from sponsoring parents, adult children, or siblings for US citizenship. The White House, led by Trump, has demanded limits on family-based immigration — which accounts for the majority of legal immigration to the US — as part of a DACA deal. The Trump framework would limit family sponsorship to “spouses and minor children” — thus presumably changing the F3 and F4 visas, used for US citizens to bring adult children and siblings, respectively, to the US, as well as an unlimited visa for citizens to sponsor their parents. (Reports indicate that people currently in line for those visas — a backlog that extends for years — will be able to remain in line.)

A report from NBC News’ Kristen Welker indicates that these family members might still be able to get visas, but wouldn’t be able to become citizens themselves — which raises as many questions as it answers about how the proposal would work.

Democrats see family reunification as an important part of the immigration system — and haven’t, thus far, been willing to entertain an overhaul of legal immigration as part of a deal to legalize only a fraction of unauthorized immigrants. The F3 and F4 visa categories account for 88,400 visas a year (even though the demand for them is far greater), and Democrats — as well as many Republicans — would rather see those visas reallocated than eliminated entirely, while immigration hawks see eliminating “chain migration” as a way to reduce overall legal immigration.

The proposed changes to family migration already have immigration advocates calling the plan “dead on arrival.” One source told the Washington Post’s Ed O’Keefe that the change would result in the lowest levels of legal immigration to the US since the 1920s.

Ending the diversity visa lottery. Few in Congress are interested in retaining the “lottery” system by which 50,000 potential immigrants from countries that don’t send many people to the US are invited to apply for admission. But many Democrats (including the Congressional Black Caucus) want to retain the “diversity” part of the diversity visa, which has been a key way for African immigrants to enter the country — a provision that Trump objected to in his instantly infamous rant about “shithole countries.”

So reception for the White House’s proposed “merit-based” replacement may depend on the details of how the replacement would actually work. (Welker’s report suggests the 50,000 visas currently reserved for lottery participants who pass standard immigration screeners would instead be used to reduce the backlogs for family-based visas and other visas.)

A “permanent solution” for DACA recipients. If the preliminary reports are correct, the White House’s proposal is much closer to the bipartisan bills Trump had rejected as too liberal on this point than to the conservative bills the White House had embraced. The framework will reportedly allow about 1.8 million people — including those young undocumented immigrants who never applied for DACA — to ultimately get green cards and citizenship. (It’s not clear how the framework would address immigrants who would have qualified for DACA but were either too old or too young.)

But Republicans might see that as a bridge too far. Conservative proposal advanced by Rep. Bob Goodlatte (R-VA) would allow only the 690,000 current DACA recipients to apply for legal status (which they’d have to meet strict guidelines to maintain), and that legal status would not lead to a green card — meaning they couldn’t become citizens unless they qualified by other means. And at least one senator, Sen. Ted Cruz (R-TX), has said flatly he won’t accept a path to citizenship for any unauthorized immigrant.

Congress spent months asking for Trump’s demands and not getting good answers

The White House put itself in this position to begin with by deciding, in September, to end the DACA program — preventing 690,000 young unauthorized immigrants from renewing the temporary work permits and deportation protections some of them had had since 2012.

Ever since September 5, when Attorney General Jeff Sessions announced that the Trump administration would end the DACA program and Trump called on Congress to address the status of DACA recipients in the next six months, members of Congress trying to work on the issue have asked the White House to tell them what kind of immigration bill Trump would be able to sign.

The White House has answered this question publicly on at least three occasions. And none of them have helped.

In October — and again earlier this month — the answer to “What do you need?” was a seven-page wish list: restrictions on legal immigration, a sweeping crackdown on unauthorized immigrants in the United States, and an overhaul of border policy (in the more recent memo, an attachment spelled out that the White House wanted $19 billion over 10 years to build a wall on the US-Mexico border). The wish list did not, however, include anything about DACA recipients — and the White House wasn’t willing to commit to supporting a bill that would allow current DACA recipients to eventually become US citizens, even if its other demands were met.

Neither of these wish lists was helpful for Republicans actually trying to come to an agreement with Democrats. Both were more or less ignored.

On January 9, in an Oval Office meeting with a bipartisan group of lawmakers, the Trump administration tried again. At first, staffers passed out a four-page list of demands compiled by the Department of Homeland Security. But Trump, reportedly upset that the list didn’t match his personal demands and that he hadn’t seen it in advance, instructed congressional leaders to ignore it. Instead, the White House issued a statement afterward saying that they’d agreed to focus the immigration debate on four issues — the same four covered in the framework the White House released on Thursday.

Will the White House become a reliable negotiating partner?

The White House’s insistence on these four pillars is a little weird at this point. Not only did they reject the only proposal that was designed to meet them (the one presented by Sens. Lindsey Graham (R-SC) and Dick Durbin (D-IL)), but they called that plan so liberal that it couldn’t even serve as a starting point for negotiations. Meanwhile, Goodlatte’s bill, which several White House figures have held up as a model, also includes several enforcement provisions that go way beyond these policy areas; if anything, Goodlatte’s bill overhauls immigration enforcement in the interior of the US even more than border security.

Congress ultimately doesn’t really need the White House to issue a policy proposal. It needs an assurance that Trump is going to pick some things that he needs out of an immigration deal, stick to them, and encourage members of Congress to get on board.

Many Senate Republicans aren’t interested in sticking their necks out for a bill that might not pass the House; many House Republicans aren’t interested in making themselves vulnerable to primary challenges by voting to offer any protections to any unauthorized immigrants. The president needs to rally his party. It’s not something he’s been able to do so far — he hasn’t even been able to make up his mind about whether he wants to make a deal on immigration even if it involves a compromise, or if he wants a radical overhaul of American immigration policy and will settle for nothing less.

Getting the president to say what he wants is the easy part; getting him to commit to it, and to try to get other people to commit to it, is much harder.