Earlier this week, Donald Trump did what he so often does in times of tense political standoff: He worked the phones with friends and allies, watched numerous hours of television punditry, and reacted viscerally to critics who said he was going limp on his hard-line promises.

This week, the warnings from the MAGA faithful were about his border wall and they stressed that the president had better hold his ground and shut the government down before bending again on funding for his big, beautiful wall.

On Thursday, Trump appeared to heed those grave warnings. Following an afternoon meeting at the White House, outgoing House Speaker Paul Ryan told reporters that the president “will not sign” the funding bill as is to keep the federal government open, citing conflict over wall money.

The president’s refusal to cave at this point, even to those in his own party who insist Republicans will be blamed for a government shutdown, was for better or worse an instructive moment of Trump’s young presidency. And it further illustrates the types of voices—the hard-line immigration restrictionists who make up so much of Trump’s political base—that hold true sway in the Trump era.

“I have said critically that the wall was the most sacred comment the president ever made,” Ed Rollins, who leads the pro-Trump political group Great America PAC, told The Daily Beast earlier in the day. “It reminds me of what George H.W. Bush said when he promised no new taxes.” Bush ended up famously reneging on that pledge, and in the next presidential election lost to Democratic nominee Bill Clinton.

Rollins added, “Trump has to be careful… His supporters care about this. This will antagonize his base if he walks away.”

Rollins, a longtime GOP and former Reagan operative, expressed similar sentiments on Lou Dobbs’s show on Fox Business earlier this week, a program President Trump regularly follows. Asked if he made his comments on Dobbs’s show assuming or hoping Trump was watching, Rollins said, “I try to give him all the best counsel I can,” though claimed he “never make[s] an assumption” Trump would see him on TV.

The president, however, has indeed absorbed the days-long spike of brutal conservative-media coverage of a possible Trump betrayal in the border wall fight, and he has reacted accordingly.

“When I begrudgingly signed the Omnibus Bill, I was promised the Wall and Border Security by leadership. Would be done by end of year (NOW). It didn’t happen! We foolishly fight for Border Security for other countries - but not for our beloved U.S.A. Not good!” Trump tweeted on Thursday morning.

But among senior Trump aides, there is a widespread, private admission that a wall covering the entirety of the southern border will, in all likelihood, never be built, according to three administration officials. And some of President Trump’s former die-hards have taken note.

Conservative author Ann Coulter—who aggressively endorsed and campaigned for Trump, in large part due to his draconian immigration prescriptions—has grown increasingly furious with the administration’s perceived lack of commitment to erecting the wall, and on Wednesday posted a column titled, “GUTLESS PRESIDENT IN WALL-LESS COUNTRY.”

Coulter wrote, “In the end, we'll probably find out ‘wall’ was Trump's ‘safe word’ with Stormy Daniels. It’s just something he blurts out whenever he’s in trouble.” The piece gained enough traction on media channels that it seemed to get the president’s attention—as of Wednesday Trump was no longer following Coulter on Twitter.

When asked by The Daily Beast if Trump deserves a 2020 primary challenger to his right, Coulter wrote back, “If there’s no wall, he’s guaranteed to lose, so it’s probably time for Trump voters to hold tryouts for a new candidate.”

Of course, Coulter is hardly the only right-wing media figure who wields outsize influence over the current leader of the free world.

On Wednesday, Rush Limbaugh also joined the chorus of hard-right lawmakers and media personalities practically begging Trump not to cave. Limbaugh vented to his millions of listeners that “Trump’s gonna get less than nothing because this compromise strips out the $1.6 billion for the wall that the Senate Appropriations Committee had already approved weeks ago.”

On Thursday afternoon, the conservative radio star claimed that President Trump personally informed him that he intends to either get wall funding or shut down the government.

“The president has gotten word to me that he is either getting money for the border, for border security, or he's shutting the whole thing down,” Limbaugh said, moments after Speaker Ryan made his own public announcement the stopgap spending bill. “The president wants you to know: it’s money or nothing,” he assured.

Trump’s former White House Press Secretary Sean Spicer told The Daily Beast, the wall brawl is “a good fight for us to have.”

But he added, “We need to message this a lot better.”

“We need to make this not just about national security, but about human trafficking and drug flows,” Spicer said. “[The wall] is a major reason Donald Trump was elected.”

Following Trump’s meeting with Republican lawmakers, Spicer’s successor Sarah Huckabee Sanders said in a statement, “Not surprisingly, they all feel strongly about Border Security—stopping the flow of drugs, stopping human trafficking, and stopping terrorism.” She continued, “We urgently need funding for border security and that includes a wall.” (The president has also signaled his willingness to accept “steel slats” in place of his original vision of a wall.)

Those statements came at the same time as another Trump policy turn that drew intense public criticism from a different GOP constituency—and in the process illustrated the elements of the Republican Party the retain sway over the president’s policy decisions, and those that do not.

The announcement this week that the United States will draw down its troop presence in Syria quickly drew condemnations and warnings of ensuing military and diplomatic bedlam. But the voices publicly calling on Trump to reverse that decision were not the same red-meat conservatives that pushed Trump to stick to his guns on wall funding.

Instead, they were more traditional, hawkish voices in the Republican Party, lawmakers like Sens. Lindsey Graham and Marco Rubio. They railed on the decision publicly, and Graham even took to Trump’s favorite medium to do so: on Thursday he pledged to tweet at the president every day until he reversed the decision.

“So hard to believe that Lindsey Graham would be against saving soldier lives & billions of $$$. Why are we fighting for our enemy, Syria, by staying & killing ISIS for them, Russia, Iran & other locals? Time to focus on our Country & bring our youth back home where they belong!” the president posted to Twitter on Thursday afternoon.

As The Daily Beast reported on Wednesday, Trump’s announcement of a Syria pullout was made hastily, with numerous defense and senior administration officials being caught off-guard, without a clear timeline or plan. One White House official compared Wednesday’s dramatic development to a mere “snap decision,” only that this particular snap decision involved war, life, and death.

But there’s no sign, at least for now, that Trump plans to reverse course—though he has before. According to people close to Trump, he sees the brand of official demanding a reversal as the precise type of Republican fossil that he crushed in 2016 and came to Washington to bend to his will.

In contrast, those calling for billions in border wall funding—at the expense of an operational federal government, if necessary—are the Trump faithful. And the border wall, more than any issue, has become a symbol of Trump’s fealty to them, and vice versa. Betraying the immigration restrictionists would be potentially disastrous for a president who built so much of his political ascent on a pledge to protect and militarize the country against a supposed invasion.

The contrast in the president’s reactions to the two different pressure campaigns was a clear distillation, in real time, of who has currently has the upper hand when it comes to White House policy.

“My strong advice to the president… is you are a separate branch of government, and you have a say-so, as well,” said Matt Schlapp, a prominent Trump surrogate and lobbyist whose wife Mercedes Schlapp is a senior White House official. “The president can’t force Democrats in the Senate [to go along], but he can veto any piece of legislation they send him and he can make the point that when it comes to the questions of the southern border, that’s he’s no longer going to take a pass, or allow Congress to take a pass.”

— With additional reporting by Lloyd Grove