Donald Trump is the most idiosyncratic Republican Party presidential nominee of the post–World War II era. A majority of political historians, I suspect, would say that his closest parallel is Wendell Willkie, another Democrat-turned-Republican businessman-turned-politician who improbably seized the GOP nomination in 1940. Nonetheless, there has emerged a cohort of Democratic commentators comparing Trump to another Republican presidential nominee: Arizona Senator Barry Goldwater, the anti-establishment conservative firebrand who led the GOP to catastrophic defeat in 1964.

Not only did Goldwater lose to Democratic candidate Lyndon Johnson in a landslide, he was so unpopular with the electorate—including a plurality of Republican voters—that he crippled his party’s candidates all the way down the ticket. The magnitude of the Republican defeat in 1964 handed Johnson the Democratic supermajority in Congress that allowed him to pass what amounted to a second New Deal. You can see why the Trump-Goldwater comparison would appeal to Democrats.

The similarities between the Republican nominees of 1964 and 2016 are more than superficial. Like Trump, Goldwater was an outsider whose nomination seemed impossible until it became inevitable. He received little support from Republicans in Congress or the party organization, but he overcame their opposition by arousing the passion of grassroots activists. His off-the-cuff speaking habit led him to make extreme statements on sensitive subjects (such as nuclear weapons) that alarmed foreign policy experts, but his partisans viewed such outbursts as evidence of his authenticity.

After presiding over a fraught convention, the prickly and headstrong Goldwater refused to pivot toward a more moderate, reassuring, “presidential” posture. Like Trump, he had no interest in reconciling with his party critics or reaching out to groups that were skeptical of the GOP, such as minorities and college graduates. He did, however, appeal to many less-educated voters in the white working class who hadn’t previously taken much interest in politics. Indeed, his campaign, like Trump’s, was predicated on the belief that a “hidden majority” of Americans would turn out to vote when they finally were offered a real alternative to the consensus politics of moderate Republicans versus moderate Democrats. Goldwater claimed to present “a choice not an echo.” That phrase became the battle-cry of his champion Phyllis Schlafly, who, before she died on September 5 at age 92, hailed the same populist potential in Donald Trump.

The Dallas Morning News recently endorsed Hillary Clinton over Trump—the first time that reliably Republican paper has declined to endorse a Republican for president since 1964 and the first time it has endorsed a Democrat for president since 1940. The Dallas Morning News objects to Trump for much the same reasons it objected to Goldwater. In 2016 as in 1964, the Republican nominee is condemned for lacking interest in the fine details of policy and government processes, for appealing to fear and stoking divisions among the electorate, and for lacking the temperament and judgment needed in a diplomat-in-chief. In 2016 as in 1964, the paper charges the Republican nominee with being, in fact, at odds with the values and ideals that have long defined the Republican Party—a verdict that has been (and will be) echoed by many other traditionally Republican media outlets.

Republican professionals today are wary of Trump’s candidacy for reasons that go beyond this election. They fear that, like Goldwater, he will not only lose badly but also alienate segments of the electorate that will never return to the GOP. They remember that African-Americans gave Republican President Dwight Eisenhower nearly 40 percent of their votes but abandoned the GOP en masse after Goldwater became one of the few Republicans in Congress to vote against the 1964 Civil Rights Act. Ever since, no Republican presidential nominee has gained more than a small percentage of the black vote. The GOP establishment is terrified that Trump, with his intemperate remarks about Mexican “murderers” and “rapists,” will make Hispanics another monolithically Democratic voting bloc. Such comments may also antagonize college graduates, who tell pollsters by overwhelming margins that they don’t want to associate with a white nationalist party.

An honest historical accounting, however, should point out the many dissimilarities between Goldwater and Trump. Start with the fact that Goldwater, unlike Trump, was an experienced politician at the time he received the GOP nomination. He was a second-term Senator who previously had played a significant role in Arizona Republican politics as a member of the Phoenix City Council. Goldwater also had laid the groundwork for his presidential campaign by chairing the National Republican Senatorial Committee, a position that allowed him to travel the country and cultivate ties with like-minded candidates. Trump, by contrast, has no direct political experience and no longstanding, loyal political network.

More importantly, Goldwater by 1964 was the unquestioned leader of the emerging conservative movement. His 1960 book, Conscience of a Conservative, was the million-selling manifesto of a political current in American politics that rapidly was acquiring money, converts, institutional infrastructure, and intellectual depth. Trump, by contrast, has channeled a populist impulse that has yet to become a movement. It’s true that his candidacy has resonated deeply with a segment of the population and has similarities with other right-wing, anti-immigrant movements in Europe. But at this point he heads a personal, candidate-centric campaign. His campaign doesn’t resemble the nascent conservative movement of the 1960s so much as the 1992 third-party presidential bid of Ross Perot or the Pim Fortuyn List in the Netherlands during the early 2000s.

While the various factions of conservatism were more or less united behind Goldwater’s candidacy, Trump’s populism cuts across all of those factions. He has laid bare the fractures within conservatism—and added new ones, by empowering the so-called alt-right. He has created schisms among religious conservatives, fiscal conservatives, neoconservatives, and libertarians. Whatever the outcome of this election, there likely will be score-settling within each faction between Trump supporters and Trump opponents for years to come. It may be a long time before conservatism can present itself as a united movement again.

We’ll have to wait for history to reveal whether Goldwater and Trump are analogous or dissimilar figures. In retrospect, Goldwater now appears a John the Baptist of modern conservative Republicanism. That is, he was rooted in a form of conservatism that had its origins in the 1920s (particularly with Republican presidents Calvin Coolidge and Herbert Hoover) and that pointed toward the movement’s fulfillment under Ronald Reagan in the 1980s.

Trump, by contrast, harkens back to some of the pre-1920s aspects of Republicanism, particularly its protectionism, anti-internationalism, valorization of the white working class, acceptance of powerful government, and emphasis on social order over individual freedom. The coming decades will reveal which of these essentially incompatible visions of the Republican Party will prevail.

Geoffrey Kabaservice is a political historian and the author of several books including Rule and Ruin: The Downfall of Moderation and the Destruction of the Republican Party, from Eisenhower to the Tea Party.

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