At first glance, the Republican Party’s latest bout of immigration infighting appears to orbit around one key disagreement: Should so-called Dreamers be given a path to citizenship?

Look a little closer, and it’s clear the rift goes far beyond Dreamers. What Republicans are struggling with is a fundamental dispute over the core values of the U.S. immigration system and who may benefit. And the same disagreements that have previously doomed the prospects of a deal threaten to do so again in this newest round of negotiations in the House.

“The future of legal immigration is the sticking point,” said Ali Noorani, executive director of the center-right National Immigration Forum. “There’s a Republican in the White House who wants to end immigration to the United States as we know it. There is not a majority of Republicans in Congress who support that position.”

Flashback to February, when the Senate took up three immigration proposals, each of which sought to meet at least some of President Donald Trump’s required “four pillars” for a deal: a solution for thousands of Dreamers, the undocumented immigrants brought to the U.S. as children; a massive investment in border security, including full funding for a southern border wall; cuts to legal immigration; and the end of the diversity visa lottery program.

The proposal that most closely matched Trump’s vision, sponsored by Senate Judiciary Chairman Charles E. Grassley of Iowa, received by far the fewest votes. The most popular, which came within six votes of passage, would have dealt with only two of the four pillars: Dreamers and border security. In other words, it would not have made any lasting changes to policy on who can or cannot eventually become an American.

Trump torched the bipartisan Senate deal via a tweet, underscoring the administration’s commitment to wholesale changes to the immigration system.

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A complete overhaul

The administration’s commitment to ending the family-based immigration system is a longtime goal of hard-line conservatives. Supporters include White House adviser Stephen Miller; his former Senate boss, Attorney General Jeff Sessions; and Sen. Tom Cotton of Arkansas, who has assumed Sessions’ mantle as the Senate’s chief immigration hawk.

While the current system prioritizes green card applicants whose relatives are already present in the United States, the hard-liners favor a merit-based system that rewards those with educational achievements and English fluency. 

“The current, outdated system depresses wages for our poorest workers, and puts great pressure on taxpayers,” Trump said in a speech to Congress last year, arguing that a merit-based system would “save countless dollars, raise workers’ wages and help struggling families — including immigrant families — enter the middle class.”

Some Democrats say something far more sinister is driving the agenda: the prospect of a whiter America. They point to an Oval Office meeting in February during which Trump, frustrated with the visa lottery program that heavily benefits African immigrants, complained of the “shithole countries” from which they hail. The United States should attract more immigrants from Norway, Trump said.

“Some people in this country would like this country to not be as diverse as it is,” Congressional Black Caucus Chairman Cedric L. Richmond said last year after Republicans unveiled a proposal that would limit green cards for refugees and eliminate the visa lottery.

For a long time, favoring a merit-based system wasn’t even a mainstream Republican belief. Sessions advocated it while he was in the Senate but made little headway, and establishment groups like the U.S. Chamber of Commerce have been resistant to the idea of moving away from the family-based system.

But by making it a key aspect of his immigration agenda, Trump is ensuring it’s now more or less the Republican Party line.

That’s what makes the latest round of immigration negotiations in the House so vexing.

It isn’t the border wall that Trump truly wants — he admitted to the president of Mexico in a phone call last year that the wall is only important politically — but rather a sweeping overhaul of the U.S. immigration system. Trump has repeatedly scuttled efforts that fall short of his goal, even if it has meant leaving the Dreamers, for whom he claims to have compassion, in limbo.

In the House

House Republicans find themselves no closer to a deal with a Tuesday deadline looming. If the GOP can’t agree on a path forward by then, it’s likely that an insurgent group of moderates will trigger automatic votes on four different immigration bills, regardless of whether leadership agrees with them or not.

One of those bills, sponsored by Judiciary Chairman Robert W. Goodlatte of Virginia and Homeland Security Chairman Michael McCaul of Texas, would get the ball rolling toward a merit-based immigration system by clearing out some of the current family-based system. It would eliminate the visa lottery, which favors individuals with historically low rates of immigration to the United States; reduce legal immigration by about 25 percent; and limit family visas to spouses and children under 18.

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Trump would likely sign the bill, which is favored by conservatives. But it has no chance of passing the Senate, where Democratic votes would be needed.

Conversely, a bipartisan bill backed by moderate Democrats and most Republicans would probably pass the House and possibly even the Senate. But the Senate outcome in February shows that such a bill has little chance of being signed into law.

For all of the optimism in the House after Thursday’s GOP conference meeting, it still remains that lawmakers in both parties would have to agree to big changes sought by Trump, starting with the end of family-based immigration and the visa lottery program.

“I think the administration wants a deal,” said Rep. Mark Walker of North Carolina, chairman of the conservative Republican Study Committee. “But at this point I don’t know that they would do anything that didn’t address those two major issues.”