OKLAHOMA CITY — Oklahoma’s conservative Republican governor, Kevin Stitt, and the state’s conservative Republican schools superintendent have appeared to stand shoulder-to-shoulder in the years of Donald Trump, with the former sending Oklahoma National Guard troops to the Mexican border and the latter stocking the state’s schools with Trump-branded Bibles.

But when the superintendent, Ryan Walters, proposed finding in Oklahoma’s schools the students living in the country illegally, Stitt said enough is enough.

“When I saw them picking on kids, I thought that’s a step too far,” Stitt said in a recent interview in his office in the state Capitol.

In an era of anything-goes politics on the nation’s right, the fight in Oklahoma may suggest there is an outer limit to what is acceptable, even for conservatives. Or it could offer a preview of the next frontier in the nation’s battle over immigration.

“It’s incredibly unfortunate that the governor has decided to undermine President Trump’s immigration agenda and take these type of swipes at him,” Walters said. “He’s attacking President Trump.”

It began when Walters, the state’s elected superintendent of schools, proposed new rules that would require Oklahoma public schools to collect citizenship information from students. The proposed rules were approved by the state school board in January, and they are now being considered by the Oklahoma Legislature.

But Stitt, no softy on immigration, lashed out immediately. He soon named replacements to the school board, whose members are appointed by the governor, so he could better resist proposals from the schools chief.

Stitt has been a strong proponent of border security, sending troops to help patrol the Texas border and lining up to support Trump’s deportation efforts. But in going after schoolchildren, Stitt said that Walters — a former high school history teacher who was once a protege of the governor — crossed a line.

“I’ve never heard Trump talk about, ‘Hey, we’re going to go after kids,’ ” Stitt said.

Stitt, who is in his final term as governor, said he had spoken with Walters and tried to talk him out of his proposal.

“You’re just trying to make a political statement, trying to get your name in the paper,” Stitt said he told him. “That’s why people hate politicians.”

Walters, who has been mentioned as a potential candidate for governor next year, has not wavered.

In his office in the state education building, he argued in an interview that his approach closely aligned with the thrust of Trump’s policies, such as ending automatic citizenship for nearly every person born on U.S. soil and allowing federal immigration agents to enter schools. An attack on the citizenship proposal, he said, was akin to an attack on the president.

Walters’ goals seem contradictory. Gathering data on the number of migrant students in Oklahoma schools would help provide language services, he said. But he also said he wants to better calculate the cost of students living in the country illegally to state taxpayers.

“My concern are the taxpayers, the citizens of the country and of Oklahoma,” he said. “Those are the people that are here legally, that voted in the elections, that need to be protected.”

His office estimated about 5,000 migrant students attend state public schools, at a cost of about $200 million a year.

Bills in several state legislatures, including in Texas and New Jersey, echo Walters’ efforts, as they seek to allow schools to collect tuition from migrant students.

Such legislation, which would probably be challenged in court, appeared to be aimed at challenging the core of a 1982 U.S. Supreme Court decision that said states could not prevent children without legal status from attending public schools.

That ruling has been a target of some Republicans in recent years, particularly as the balance of power on the Supreme Court has shifted in favor of conservatives.

Walters said he favored overturning the precedent. Stitt said he did not.

Jackson Lahmeyer, a pastor in Tulsa, Oklahoma, and a member of Trump’s newly created White House Faith Office, said he liked both the governor and the school superintendent, but sided with Walters on collecting student citizenship data.

“This is the agenda of the president who won,” said Lahmeyer, whose church has attracted members of Trump’s family and administration. “We need to know if students are U.S. citizens or if they’re not.”

Stitt said he did not object to enforcing immigration law but worried that parents living in the country illegally would potentially keep their children home, rather than be forced to disclose their immigration status.

“The kids didn’t do anything wrong, is my point,” he said.

Stitt, a mortgage company entrepreneur who was first elected in 2018, suggested a better solution involved fixing the immigration system — an idea that harked back to the pre-Trump Republican Party of George W. Bush — so that companies who want to sponsor foreign workers could legally do so more easily.

The Oklahoma citizenship proposal must still be considered by the Legislature before the governor has a chance to formally block it.

Privately, Republicans in the Legislature have chafed at the measure, said Tyler Powell, a Republican political consultant in Oklahoma. Publicly, they have mostly avoided the fray. The leaders of the state House and Senate did not respond to requests for comment.

Powell said the rightward shift in Republican primaries in 2024 has many worried about angering Walters, who is popular with the state’s core Republican base.

“Everyone has a little bit of a fear of Walters,” he said. “Behind the scenes, they have ensured that Walters’ policies don’t go through, but they don’t want to come out and walk a plank with their voters.”

Walters has gained attention nationally for his efforts to introduce religious and Trump-branded conservative instruction into public schools, garnering praise from religious conservatives and those strongly aligned with Trump. He has moved to purchase Bibles for public schools, to create of a religious charter school and to alter state curriculum to teach the “discrepancies” in the 2020 election, among other things.

“My opinion is Walters needs to stop trying to gain the attention of the president and do his job,” said Mark McBride, a former Republican member of the Oklahoma House who worked on education issues. “I hope that Gov. Stitt will continue to push back on the superintendent.”