As Washington barrels towards another immigration showdown, the fate of nearly two million people brought to the US illegally as kids, who face the loss of work and study privileges and even deportation again rests on the President.
The repeated tussles over the fate of people protected by the expiring Deferred Action for Childhood Arrivals program have shown that only the President has the weight and political capital to ultimately frame a deal on treacherous political ground and to sell it to grassroots GOP voters.
It's also obvious that opening an eventual pathway to citizenship for such people -- even in return for substantial funding for the border wall, an idea that electrified his 2016 campaign -- would risk his standing among his most loyal supporters.
It's not yet clear Trump is yet ready to pay that price. In fact, the President seems to be going in the opposite direction.
Launching a new round of brinkmanship, Trump warned Tuesday that he was ready to plunge the country into another government shutdown if he doesn't get Democrats to sign up to tough new immigration laws.
"I'd love to see a shutdown if we can't get this stuff taken care of," Trump told reporters at the White House.
White House chief of staff John Kelly meanwhile took aim at undocumented immigrants who had not taken advantage of a government scheme to shield them under the Obama administration, calling them "afraid" or "lazy."
It was not immediately clear whether the new assault by the White House was an expression of frustration directed towards Democrats who have refused to accept the President's hardline offer on immigration or an attempt to stake out a tough negotiation position that could be refined later.
Often, Trump acts out of instinct and rather than according to well-planned strategies. Sometimes, he has appeared unsure how to move forward on an issue where he is under intense pressure from both sides. On immigration, he has expressed "love" for the undocumented immigrants concerned. But he also ended the program initiated by former President Barack Obama that granted them protections.
Trump's threat on Tuesday also seemed strangely detached from tortuous negotiations taking place on Capitol Hill on a two-year spending bill -- talks which finally appear to be edging towards success -- partly because they are insulated from the threat of a shutdown caused by the immigration imbroglio.
It also directly conflicted with the message of unity and compromise that he preached in his State of the Union address just a week ago.
But the outbursts did serve to underscore the fundamental point that there can be no immigration deal without the President becoming an integral part of the process at a time when there is still uncertainty about his position.
"We need the wall. We're going to get the wall. We don't have the wall, we're never going to solve this problem," Trump said at a White House event dedicated to threat of MS-13 gangs. "I would shut it down over this issue. I can't speak for everybody at the table but I will tell you, I would shut it down over this issue."
Throwing delicate talks off balance
Trump's threats recalled previous episodes in which Republican and Democratic leaders edged towards a deal on key issues like immigration and government funding -- only for the President to unravel it with his comments.
One reason why his remarks caused such consternation is that immigration is not part of the funding deal being worked on in Congress, which would hike military and other spending and could end the constant sequence of funding battles and government shutdown threats for the next two years.
It was not clear whether the President was not up to speed on those negotiations or he was seeking to reintroduce the issue of immigration into the spending fight -- a tactic which caused last month's shutdown.
"As we get close to agreement, the President steps in and makes it very difficult to get our job done," Maryland Sen. Ben Cardin told CNN's Wolf Blitzer on the "Situation Room."
But the consternation that immediately rippled through Washington following Trump's shutdown declaration showed the crucial nature of his role.
The White House has proposed four pillars for immigration reform, including the quid pro quo of protection for DACA recipients in exchange for border wall funding. But it also demanded new limits to legal immigration with reforms to family migration and changes to the visa lottery system.
The latter two proposals are unacceptable to Democrats -- and to some moderate Republicans facing re-election in competitive districts in 2018 -- making them unlikely to pass the Senate.
Hopes for a Senate deal now hinge on a wide-ranging debate that Senate Majority Leader Mitch McConnell has promised for next week.
The problem, however, is that even if the Senate agrees a deal, it must pass the House of Representatives, where conservative sentiment on is more radical on the issue and is unlikely to swallow the other chamber's compromise.
This is where the President comes in.
Ryan in lockstep with the President
On Tuesday, House Speaker Paul Ryan summed up the daunting prospects for any deal by warning that nothing moves unless Trump says it does.
"We're working on something here in the House. We're working on bipartisan negotiations. It's going to be a bill that we support and the President supports," Ryan said at a news conference.
One enthusiast for reform, Sen. Lindsey Graham, R-South Carolina, warned he was "increasingly pessimistic" that anything other than a "punt" to protect DACA recipients for a couple of years was now possible.
There's just one thing that could unpick the deadlock. A concerted effort by Trump to give Republican lawmakers in the House in particular political cover to shield DACA recipients, a tough vote for many ahead of primary season.
It was that kind of intervention that Ryan's comments on Tuesday appeared to be holding out for.
Some immigration advocates, hearing Trump's frequent offers to help DACA recipients, had hoped a Nixon to China scenario could unfold had Trump used the political capital he had built up with supporters with his hardline immigration stands in 2016 to coax legislation over the line.
But when Trump offered a path to citizenship for DACA recipients as part of his four pillars offer last month, he was branded "Amnesty Don" by Breitbart News, which casts itself as the voice of his populist, nationalist movement.
Tuesday's developments suggested that the President is not yet at a point where he is ready to risk paying the price of alienating his base.
Until he is, an immigration reform compromise seems unlikely.