The split defines the modern Republican party, as the old fiscal conservatives battle the new-right populists for control of the movement.

Some would call it another perfect call.

And as soon as Senator Hawley hung up the phone, the Missouri Republican rushed to social media to report on the “great talk” he just had and the promise President Trump made about the One Big Beautiful Bill, the cornerstone of his second term domestic policy agenda: “NO MEDICAID BENEFIT CUTS.”

Mr. Trump has said as much publicly, but the message still reassured the senator as Republicans on Capitol Hill search for savings to make up for federal revenue lost to tax cuts. Quickly emerging as the most vocal GOP opponent to Medicaid cuts, Mr. Hawley has warned his business-friendly colleagues that their mega bill amounts to a referendum: They can be either the party of the working class or the corporate C-suite .

The president put it more bluntly. “People who cut Medicaid and Medicare lose elections,” Mr. Trump told Mr. Hawley according to the senator. “My advice,” he said in an interview with RealClearPolitics, “listen to the guy who won the popular vote.”

Asked about the conversation, White House spokesman Kush Desai repeated Mr. Trump’s long stated policy preference. “The President has been clear—no cuts to Medicare, Social Security, or Medicaid,” Mr. Desai said in a statement to RealClearPolitics, adding that the bill “addresses waste, fraud, and abuse in government spending.”

Normally this would be the final word. Mr. Trump has remade the party in his image, and he gets his way more often than not. Yet the battle over Medicaid reform comes when the federal debt exceeds $36 trillion, and after Moody’s downgraded America’s sovereign debt rating, and as interest payments to service that debt exceed federal spending on national defense. According to Congressional Budget Office estimates, Medicaid, the largest health American insurance program, will cost nearly a trillion dollars annually within the decade.

Hence the mocking all-caps rebuttal from Representative Chip Roy.

The Texas Republican wrote that he had his own “great talk,” not with the president, but his children, who said, “STOP BORROWING MONEY TO PROP UP WASTEFUL SPENDING & TO SUBSIDIZE THE ABLE-BODIED OVER THE VULNERABLE.” Replied Senator Lee of Utah, one of the few remaining GOP fiscal hawks, “Your kids aren’t wrong.”

Such is the split that defines the modern GOP, as the old fiscal conservatives battle the new-right populists for control of the movement. The dry text of the tax bill doesn’t make compelling reading. The intricacies of the legislation, and then all the outside analysis attempting to explain those details, can certainly be confusing. Yet the result of the fight, the direction the GOP takes, will be telling.

“We’re about to learn whether or not Republicans want to be a majority party,” Mr. Hawley insisted.

While the White House insists the mega bill “is the most essential piece of legislation currently under consideration in the entire Western World,” the proposed spending cuts to Medicaid are starting to overshadow the new border security and tax cuts they were designed to pay for. Republicans now have the most consequential fight over health care since Obamacare repeal on their hands. And just like 2017, the margins are again slim; the majority leader, Senator Thune, can afford to lose only two votes.

Yet the party has changed considerably since then. With Mr. Trump at the helm during the last election, Republicans increased their voting share with every major demographic. The “multiethnic, multiracial, working class” coalition that the former senator representing Florida, Marco Rubio, once envisioned seems within the GOP’s grasp. Screwing it up by “considering” cuts to the social safety net, Mr. Hawley said, wouldn’t only be “insane.” He warns his party that it is “suicidal.”

This befuddles the likes of Speaker Johnson, who defended the cuts in an interview with NBC’s “Meet the Press” earlier this month by arguing that “4.8 million people will not lose their Medicaid unless they choose to do so.” It isn’t a cut, the speaker argues, so much as a structural reform to root out waste, fraud, and abuse.

The House bill that Mr. Johnson shepherded requires able-bodied adults without dependents to work, study, or volunteer for at least 80 hours per month to keep their coverage. It also includes new eligibility requirements which Republicans say are meant to keep illegal immigrants off Medicaid. Another big reform, the bill would freeze so-called provider taxes, a practice employed by 49 states that the New York Times describes as a “Medicaid loophole” which allows individual states to use taxes to inflate their spending, thus increasing their federal reimbursement.

The populist isn’t opposed to everything House Republicans passed over to the Senate. Work requirements — Mr. Hawley said he supports them “wholeheartedly.” And making illegal immigrants ineligible for benefits, he added, “I’m absolutely for that 100%.” The provider tax, however, he finds “problematic” and worries it could lead to the closure of rural Missouri hospitals.

Congress has not yet reached the beginning of the end of the sausage-making (a fact that makes pinning lawmakers down difficult). The House version of the bill can and will change. Rather than picking apart that text, Mr. Hawley said he is focused on influencing the Senate bill and ensuring that “it is in line with the commitments that the president has consistently articulated.”

The general Hawley redline: “What I don’t want to see, and what I’m not going to vote for, is anything that will result in benefit cuts to folks who are otherwise eligible, and for working people, in my state.”

Even with slim majorities, Republicans have a free hand to pass the bill using budget reconciliation, a parliamentary process that requires 51 votes rather than the normal 60-vote supermajority. All the same, they are tied up in knots by a new more populist coalition. Warned Steve Bannon, an early architect of Trumpism, “MAGA’s on Medicaid because there’s not great jobs in this country.”

A familiar fracas has ensued. “The current budget is a rare, maybe once in a generation, chance for a significant Medicaid policy victory,” opined the Wall Street Journal editorial board earlier this year. Yet to the horror of that business-friendly paper, Mr. Hawley and his Medicaid redline threatened to tie up the GOP. Wasn’t this the same senator who as Missouri attorney general once joined a 2018 lawsuit to repeal the Affordable Care Act and its Medicaid expansion, they asked, dubbing the evolution “the Josh Hawley Medicaid Switcheroo.”

“This is not about Obamacare,” Mr. Hawley replied when asked about that criticism. “This is about protecting working people and Medicaid.”

More than a million Missouri citizens rely on the program for insurance, and despite strong opposition from Republicans particularly in rural areas, the state voted through a ballot measure to amend the Constitution and expand Medicaid. “I represent the state of Missouri. I don’t represent Wall Street,” Mr. Hawley said referencing that recent history, “and I certainly don’t represent the Wall Street Journal editorial board.” He then added, “I’m sure that those who are in the business of making money by strip mining this country would love to gut Medicaid.”

Conservatives have long hoped to trim the social safety net. Some want steeper reductions. All in all though, there is a feeling in more orthodox corners of the GOP, like the conservative National Review, that the House bill represents a good compromise. In a recent editorial, that magazine opined that the cuts were more akin to “a modest series of tweaks” which will “not do much to alter its spending trajectory.” According to the Congressional Budget Office, the House reforms will reduce Medicaid spending by about $723 billion over the next decade and reduce total enrollees in the program by 7.6 million.

Mr. Hawley isn’t deaf to those debt arguments. If Republicans really want to save money on healthcare, though, he said that his party ought to look to the president. More specifically, the senator pointed to Trump’s proposed policies to cap the cost of prescription drugs and to close the so-called carried interest loophole. Those he says, “would save a bunch of money.”

Of course, as Mr. Hawley well knows, those proposals would kick up their own firestorms on the right. Yet his point remains: There are other avenues. “If people are serious about wanting to actually save money, there’s all kinds of ways to do it,” Mr. Hawley said. “But my point is, let’s not tell working people that we just can’t help them. ‘Sorry! We’re going to have to take away your benefits because there’s a corporate guy out here who wants his thing to be permanent!’”

That is the old GOP way of doing things, and in his estimation, it leads to political obscurity.

“If we’re not interested in being a majority party, then we’ll keep doing the things that the party’s done for decades,” Mr. Hawley concluded, “And you know, we’ll bow to corporate interests and let them write the bill.” His suggestion, the one giving Republican brass fits right now, is instead to “just go back and listen to what Donald Trump said on the trail over the last year.”

This article was originally published by RealClearPolitics and made available via RealClearWire.