Ruth Ben-Ghiat is a frequent contributor to CNN Opinion and a professor of history and Italian studies at New York University who writes about authoritarianism and propaganda. Follow her @ruthbenghiat. The opinions expressed in this commentary are solely those of the author. Read more opinion articles on CNN.

(CNN) "Are black and yellow people at our doors?" Fascist dictator Benito Mussolini asked this question in 1927, two years into his dictatorship -- and his answer was yes. He falsely proclaimed a population emergency for "the entire white race" that threatened not only Italy but all of Western civilization.

Ruth Ben-Ghiat

A straight line links this fascist rhetoric and the racist pronouncements regularly made by Rep. Steve King, R-Iowa, who is back in the news for asking : "What if we went back through all the family trees and just pulled those people out that were products of rape and incest? Would there be any population of the world left if we did that?" He made this staggering statement matter-of-factly, as part of a defense for not allowing exceptions for abortion in cases of rape or incest (the gist of the anti-abortion legislation he unsuccessfully tried to have passed in Congress). Its implication is clear: every white birth matters when the "real" America is under siege from peoples of color, an argument King has made before. "We can't restore our civilization with somebody else's babies," King famously wrote in 2017, retweeting the anti-Muslim and anti-immigrant Dutch rightist Geert Wilders while wishing for an America "that is just so homogeneous that we look a lot the same." In his 2017 comments about "somebody else's babies," King also linked the "civilization" he was talking about with keeping the "birth rate up" -- a connection often made by white nationalists in the US and Europe.

Congresswoman Liz Cheney , R-Wyoming, and a host of other prominent Republicans hurried to denounce him, but no matter who calls for his resignation, Republicans can't avoid the fact that King's brand of white nationalism is now firmly ensconced in the White House and in the political culture the GOP has enabled. King's abortion measure had the support of the GOP. Abortion bans under any circumstances have become an increasingly mainstream position, thanks to the presence of Christian Evangelical-supported Vice President Mike Pence and the proliferation of statewide-measures to that effect. It's worth noting as well that King did not make his latest racist comments to a gathering of far-right extremists, but at the Westside Conservative Club in Iowa.

JUST WATCHED Rep. King insists he's not racist Replay More Videos ... MUST WATCH Rep. King insists he's not racist 04:47

In fact, the need to defend "Western civilization" from threats by people of color isn't just a callback to fascism -- it is now an established latest White House and GOP talking point. It's used not just by the administration's architect of anti-immigration policy, Stephen Miller -- who excuses Trump's racist attacks against Alexandria Ocasio-Cortez, D-New York, and other congresswomen of color as a defense of "the principles of Western civilization" -- but by Cheney herself. Earlier this month, she accused indigenous peoples and environmentalists who prevailed in court to restore protections to the grizzly bear in Greater Yellowstone as "intent on destroying our Western way of life," a statement that may seem to refer to the American West, but resonates with the right's attacks on the cultures of indigenous peoples in Jair Bolsonaro's Brazil as well.

GOP luminaries, afraid of alienating voters in the 2020 election, may find King a convenient scapegoat, but it will become more and more difficult for them to deny that racism is an ideological and policy space where the President's own long-held beliefs mingled with those of his heterodox group of backers, who represent important Republican constituencies.

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