Former Vice President Mike Pence devoted an entire speech on Wednesday to what he called a “fundamental” and “unbridgeable” divide within the Republican Party — the split between Reaganite conservatives like himself and propagators of populism like former President Donald J. Trump and his imitators.
Mr. Pence, who is polling in the single digits in the G.O.P. presidential primary race and lags far behind the front-runner Mr. Trump, has been warning about the dangers of populism for nearly a year. But his speech on Wednesday went further than he has gone before, casting Mr. Trump’s populism as a “road to ruin.”
“Should the new populism of the right seize and guide our party, the Republican Party as we have long known it will cease to exist,” Mr. Pence said at the New Hampshire Institute of Politics at Saint Anselm College in Manchester. “And the fate of American freedom would be in doubt.”
In his plea to Republicans to abandon populism and embrace conservatism, Mr. Pence said that “we have come to a Republican time for choosing.” The line echoed his hero Ronald Reagan’s 1964 televised address, “A Time for Choosing,” in which the former Hollywood actor framed that year’s presidential election as a choice between individual freedom and governmental oppression.
“Republican voters face a choice,” Mr. Pence said. “I believe that choice will determine both the fate of our party and the course of our nation for years to come.”
He asked if the G.O.P. will be “the party of conservatism or will we follow the siren song of populism unmoored to conservative principles? The future of this movement and this party belongs to one or the other — not both. That is because the fundamental divide between these two factions is unbridgeable.”
Mr. Pence defined Republican populism as a trading away of time-honored principles for raw political power. He said populists trafficked in “personal grievances and performative outrage.” And he said they would “abandon American leadership on the world stage,” erode constitutional norms, jettison fiscal responsibility and wield the power of the government to punish their enemies.
He connected Mr. Trump’s populist movement to a long line of progressive populists, including Senator Bernie Sanders of Vermont and Huey Long, the former governor of Louisiana. He said that progressivism and Republican populism were “fellow travelers on the same road to ruin.”
And Mr. Pence named names.
“Donald Trump, along with his imitators,” he said, “often sound like an echo of the progressive they would replace in the White House.”
In response to Mr. Pence’s speech, Jason Miller, a senior adviser to the Trump campaign, said in a statement, “President Trump’s victory in 2016 exposed the massive divide between voters around the country and the establishment Beltway insiders who made terrible trade deals, allowed our southern border to become overrun and never missed an opportunity to play world cop. The conservative movement and the Republican Party have changed for the better, and nobody wants it to go back to the way it was before.”
Mr. Pence, in his speech, also called out Gov. Ron DeSantis of Florida for using state power to punish corporations for taking political stands he disagreed with — a reference to Mr. DeSantis’s efforts to strip Disney of its special tax status.
Mr. Pence said he understood the frustrations that had led to populist movements both on the left and the right. He listed income inequality caused by globalization and increased automation, the opioid epidemic and the cultural demonization of conservatives. He did not include on his list the invasion of Iraq — which, unlike most Republicans, he still defends to this day.
But he glossed over his own role in promoting Trumpism as Mr. Trump’s vice president as well as his traveling booster, a role Mr. Pence served throughout the 2016 campaign and all four years of the Trump presidency. Mr. Pence finally broke with him by refusing Mr. Trump’s demand that he overturn the results of the presidential election on Jan. 6, 2021.
In Mr. Pence’s telling, it is Mr. Trump who has changed. He said Mr. Trump ran as a conservative in 2016 and governed as one with Mr. Pence’s help. But that story ignores inconvenient facts, including that the Trump-Pence administration added around $8 trillion to the national debt, enacted a protectionist trade policy and laid the groundwork for a complete withdrawal of U.S. troops from Afghanistan that Mr. Pence opposed.
The former vice president has woven warnings about populism into many of his speeches and off-the-cuff remarks since at least last October, when he condemned “Putin apologists” in the Republican Party. But at the first Republican debate last month in Milwaukee, the split between New Right populism and Reaganite conservatism came under a brighter spotlight in the onstage clashes between Mr. Pence and the businessman Vivek Ramaswamy.
In recent weeks, Mr. Pence and his team decided the subject was important enough to warrant its own speech, according to a person familiar with the planning, who was not authorized to discuss it publicly. His invocation of Mr. Reagan as an inspirational figure — a common theme of Mr. Pence’s speeches but done at length on Wednesday — comes as Mr. Pence and other Republican presidential candidates prepare for their second debate, which will be held on Sept. 27 at the Ronald Reagan Presidential Library in Simi Valley, Calif.
As he extolled his hero, Mr. Pence all but pleaded for Republicans to remember there was a time before Mr. Trump. And that it was a time worth returning to.
“The truth is,” he said, “the Republican Party did not begin on a golden escalator in 2015.”