It's the campaign promise that Republicans just can't shake.
President Donald Trump is insisting that his "big beautiful" border wall be part of any deal to protect hundreds of thousands of young immigrants from deportation.
President Donald Trump campaign on a promise to build a physical border wall
For more than a year, Republicans have tried to downplay the issue
'The wall is a necessary part of this deal because the President campaigned on it'
As congressional negotiators forge ahead with plans to shield recipients of the Deferred Action for Childhood Arrivals program from deportation ahead of a March deadline, Republicans and Democrats are grappling with how to give Trump a symbolic win without sabotaging a compromise they've been carefully and sincerely crafting for months.
For more than a year, Republicans have tried to downplay Trump's border wall, ignore it, even blast it. Members of the GOP who have spent decades on immigration reform have reiterated time and time again that a border wall is hardly the most effective way to secure the border.
"If you only build a wall, only a 'wall,' without using technology, individuals, drones, observations, etc., you're not going to secure the border," Sen. John McCain told CNN in February 2017.
"I don't think we're just going to be able to solve border security with a physical barrier because people can come under, around it and through it," said Sen. John Cornyn, R-Texas, told CNN at the time.
But, the wall and the President's appetite for it hasn't gone away.
On Friday, the Trump administration requested Congress spend $18 billion over the next 10 years to construct the wall. And over the weekend, Trump told reporters "we all want DACA to happen, but we also want great security for our country."
The wall now represents a complicated political question for Republicans and Democrats. How can the GOP give Trump a win on the wall without alienating Democrats from a bipartisan solution on DACA?
The answer may be in semantics.
"I think it's a mistake to think of the border wall as a standalone," Cornyn, the No. 2 Republican in the Senate, told CNN Monday. "It is part of a system that will include technology and include more border patrol and it's going to have to be integrated along the entire border and northern border as well so yeah, it's going to be part of it, but what I want to see is a comprehensive security solution and not just focus on one component."
The kind of "wall" many Republicans believe is realistic varies greatly from the hundreds-of-miles-long concrete barrier that Trump may have imagined when he campaigned for President.
Ahead of a bipartisan meeting at the White House Tuesday, the question is becoming whether Democrats can accept some version of a wall (albeit they'd call it something else) in exchange for protections for those who are eligible for DACA. And, if Republicans can convince Trump to accept more money for border security overall as a win on the wall.
But Democrats have long drawn a line in the sand on the wall, defeating funding it at every turn so far. Wall funding wasn't included in a stopgap year-end funding bill, nor was it ever considered when Democrats thought they'd struck a deal on DACA with Trump this fall.
If Republicans see the wall as little more than symbol of broader border security, the Democratic base has come to accept it as the ultimate concession to Trump, a physical reminder of Trump's harshest immigration policies.
Congressional leaders met with Trump at the White House last Thursday, but Senate Minority Leader Chuck Schumer said the President's call for a wall to be part of the deal may have poisoned the well.
"Unfortunately, following that meeting, the White House issued a series of unreasonable demands entirely outside the scope of our ongoing negotiations about DACA and border security," Schumer said on the Senate floor Monday.
"To throw down a list from the hard, hard-line wing of the White House is not a very fortuitous or smart thing to do," he added.