White supremacism was never banished from American political thought, just shoved to the fringe and hushed to a whisper. Now, in the Age of Trump, it’s back in the mainstream and ready to roar.

Witness the words of Rep. Steve King (R-Iowa) on the subject of immigration: “Culture and demographics are our destiny. We can’t restore our civilization with somebody else’s babies.” King offered these sentiments Sunday in a tweet expressing solidarity with Geert Wilders, an openly racist and Islamophobic Dutch politician who has a chance of becoming prime minister in elections this week. Wilders is someone who “understands,” King wrote.

And we understand just what King meant. Former Ku Klux Klan leader David Duke certainly got the message, using his vile Twitter account to proclaim, “GOD BLESS STEVE KING!!!”

Just so there’s no confusion, King went on CNN Monday to say that “I meant exactly what I said.” He added: “I’ve been to Europe and I’ve spoken on this issue and I’ve said the same thing as far as 10 years ago to the German people and any population of people that is a declining population that isn’t willing to have enough babies to reproduce themselves. I’ve said to them, ‘You can’t rebuild your civilization with somebody else’s babies. You’ve got to keep your birthrate up and you need to teach your children your values.”

Why am I hearing faint strains of “Deutschland über alles”? And why am I not hearing a loud chorus of condemnation from King’s Republican colleagues?

King told CNN that he is merely “a champion for Western civilization,” which he called “a superior civilization.” Which means, of course, that he considers other civilizations inferior. But we knew that.

After all, King has a history of inflammatory immigrant-bashing. In 2013, he said that for every undocumented immigrant who becomes a valedictorian, “there’s another hundred out there that — they weigh 130 pounds, and they’ve got calves the size of cantaloupes because they’re hauling 75 pounds of marijuana across the desert.”

And as for race, a guy from Iowa who keeps a Confederate battle flag on his desk is definitely sending some kind of message. He tried unsuccessfully to block the federal government’s plans to remove Andrew Jackson’s image from the $20 bill and replace it with that of Harriet Tubman. King says he is proud that some of his ancestors were abolitionists. One wonders whether he knows what the word means.

We should pay attention to his lexicon, however, because today’s white supremacism tends to shy away from overtly racial terminology. Listen instead for words such as “culture” and “civilization.”

The idea is that the United States is the land of the free and the home of the brave because its “civilization” is “European” or “Western” — euphemisms, basically, for “white.” According to this view, immigrants have been assets to the country only to the extent that they have fully assimilated into the dominant culture. And while previous waves of immigrants may have become part of the fabric of our society, recent Latino immigrants are not blending in. And as for Muslims, well, forget about it; the Constitution may forbid the establishment of any official religion, but our civilization is resolutely Christian. African Americans are okay so long as they accept the foregoing as true — and do not assert any sort of distinct African American identity.

I think that’s a fair reading of modern white-supremacist doctrine. Of course, it’s a bunch of racist, ahistorical claptrap.

Immigrants — both voluntary and involuntary — have shaped this nation since long before its founding. The first Africans were brought here in bondage in 1619, one year before the Mayflower. Americans have never been a single ethnicity, speaking a single language, bound by the centuries to a single patch of land. We have always been diverse, polyglot and restless, and our greatness has come from our openness to new people and new ideas.

King’s distress about birthrates can be read only as modern-day eugenics. If he is worried about the coming day when there is no white majority in the United States, he has remarkably little faith in our remarkable society — or in the Constitution that he, as a member of Congress, is sworn to support and defend.

President Trump played footsie with the white supremacist movement during his campaign. His chief strategist, Stephen K. Bannon, waged civilizational war when he ran the Breitbart News site. Trump could definitively denounce King’s racism with a statement or a tweet, but so far his silence is deafening.

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