A political pressure group recently announced that it plans to spend upwards of a million dollars on a campaign to get Congress to pass legislation protecting immigrants who were brought illegally to the United States as children — the so-called “Dreamers” — from deportation. Last month, the group launched a TV ad to build support for a bill that would enact Deferred Action for Childhood Arrivals policy, or DACA, into permanent law. Last week, it kicked off a direct-mail blitz, sending flyers to 100,000 households, applauding members of Congress who have come out for the bill. Among the members being singled out for praise are four House Democrats from New Mexico and California, along with Democratic Sen. Chris Coons of Delaware.

This effort to influence the immigration debate by undercutting hard-line Republicans isn’t coming from deep-pocketed liberals. It is being funded by industrialists Charles and David Koch, who over the years have poured vast amounts of money into electing GOP candidates and advancing conservative causes.

In the demonology of the Left, the Kochs are tantamount to Satan. Elizabeth Warren, Bernie Sanders, and Democratic strategists regard them as the embodiment of political wickedness. From bankrolling the Tea Party to assailing the Affordable Care Act to waging war against Barack Obama, the Kochs have been a powerful force on the Right. Why now have they suddenly gone rogue?

They haven’t.

The billionaire brothers aren’t turning their backs on principled Republican conservatism — they are upholding it. It isn’t a betrayal of traditional GOP attitudes toward immigration to encourage lawmakers to end the legal limbo in which 1.8 million “Dreamers” have been trapped. It is a reinforcement of those attitudes.

President Trump, a man of few fixed ideological principles, has been all over the map on DACA’s future. He announced last September that he would revoke DACA in its existing form — it’s merely an executive order signed by Obama — and gave Congress six months to enshrine the policy into a permanent law. He spoke warmly about Dreamers, saying that he has “a great love for them” and urging Congress “to help them and do it properly.” In January, he invited a bipartisan group of legislators to the White House and said he was eager to sign a straightforward DACA bill right away.

More recently, however, he turned hostile. “NO MORE DACA DEAL,” he tweeted, claiming that migrants from Latin America are “coming in because they want to take advantage of DACA.” When a compromise was proposed in Congress in February — it offered eventual citizenship for the Dreamers and set aside $25 billion for enhanced border security — the White House shot it down.

Now a coalition of Republicans and Democrats in the House is trying to break the impasse by means of a discharge petition. The parliamentary maneuvering is complicated, but if the petition gathers 218 signatures, House leaders will be forced to bring a DACA bill to the floor for a vote. Most Democrats are likely to sign, but Republicans are being heavily pressured not to do so, on the grounds that a vote for “amnesty” — i.e., for protecting Dreamers once and for all — will infuriate the Trumpist base and depress Republican turnout in November.

It’s against this background that the Kochs are ramping up support for a DACA fix. And they aren’t the only ones. Politico reports that former Exelon chairman John Rowe, a Republican mega-donor who has funneled hundreds of thousands of dollars to GOP candidates, “is threatening to choke off campaign resources” to congressmen who refuse to sign the discharge petition. “There’s a whole bunch of Republicans like me,” Rowe said he told Rep. Steve Scalise, the House majority whip, “who simply aren’t going to keep giving money if you don’t get an immigration bill done.”

Extending permanent legal status to Dreamers may be anathema to seal-the-border restrictionists, but for most voters it is a no-brainer. A strong majority of voters, including most Republicans, has consistently told pollsters that DACA enrollees and Dreamers should be granted a path to citizenship, not threatened with deportation. Outside the fever swamps, there could hardly be a more mainstream position.

Nor, in historical terms, could there be a more Republican one.

For most of its existence, the Party of Lincoln was the party of immigration. The GOP platform of 1864 ringingly declared that “foreign immigration … should be fostered and encouraged by a liberal and just policy.” Nearly a century later, when Richard Nixon first ran for president, his party called for opening the nation’s gates even wider. Citing “Republican conscience and Republican policy,” the 1960 platform urged that “the annual number of immigrants we accept be at least doubled.”

Pursuing the GOP nomination in 1980, Ronald Reagan and George H.W. Bush spoke with compassion and warmth about immigrants — even those here illegally. “Rather than talking about putting up a fence,” Reagan suggested, “why don’t we … open the border both ways?” As president, Reagan championed a path to citizenship for millions of undocumented immigrants; he always envisioned America, he would say in his farewell address, as a land whose “doors were open to anyone with the will and the heart to get here.”

Admittedly, there has always been a nativist strain in American culture, and more than a few Republicans plainly share Trump’s immigration sourness. But they don’t reflect the Republican conservative tradition. It is Rowe and the Koch brothers who are being faithful to the GOP heritage, and the anti-DACA bitter-enders who are betraying it.

Jeff Jacoby is a columnist for The Boston Globe.