Donald Trump knows a thing or two about “shitholes” – the label he apparently bestowed on El Salvador, Haiti and various African nations during an Oval Office meeting about immigration. His own father was reportedly so ashamed of coming from Germany – widely considered to be a “shithole” by Americans fighting in two world wars – that he pretended for most of his life that he was Swedish.

These Aryan dreams glowed all blond and bright through Trump’s seminal book, The Art of the Deal, in which he claimed his father arrived as a child from Sweden like some kind of Nordic dreamer.

And they persist to this day inside the White House, where the 45th president of the United States wonders why oh why can’t we get more Norwegians to restock the racial purity of our immigrant bloodlines?

Before the Finns complain about prejudice, we need to have a frank discussion, Mr President.

You don’t need to be ashamed of your own “shithole” past. Like you, my family also hails from a “shithole”. Half my family comes from Morocco, which is an African country. Like you, I was even born in a “shithole” part of a nation that was once frequented by Viking invaders. I grew up in Birmingham, which you might think of as the Queens of England. (Memo to the White House: Not the Queen of England. She’s totally different, although she’s also from a German family.)

Just as all those snooty Manhattan types disdain your birthplace, most of London sneers at mine. I feel your pain. Us shitholers need to stick together. There’s hope for us, you know. You became president because your Russian friends thought you’d be good for a giggle. I learned how to read and write, and chanced upon a job as a typist. It’s funny how immigration opens doors like that.

Far too many people are surprised by your racism, which is as ignorant as it is blatant. This is confusing because you’ve made no secret of your attitudes.

You started this political trip by insisting that America’s first black president wasn’t really American, despite all evidence to the contrary. You seem driven by an irrational hatred of everything Obama: you even blamed him on Thursday for building a new US embassy in London, even though the decision was taken by his white Republican predecessor. You campaigned against Mexico by peddling the libel that the country was sending its criminals and rapists to America. You now want to kick out 200,000 immigrants from El Salvador who keep the economy humming in your new hometown of Washington.

When neo-Nazis marched in Charlottesville, carrying torches and shouting about racial purity, you said they were good people. You endorsed the Britain First brand of neo-Nazism by sharing its racist lies on Twitter.

With a depressing frequency, you have made it clear that you are literally a neo-Nazi sympathizer. If at some stage you promote eugenics on Twitter, we will save a few letters on our character counts and simply call you a neo-Nazi.

For now, your power to shock says more about us than it does about you. Some people were genuinely ready to believe you were considering a deal on immigration after you allowed the TV cameras to broadcast your civil discussion inside the cabinet room on Tuesday. The media seemed surprised that you could speak like a sane person without dribbling on to your shoes.

This is of course a low bar. But so is feeling outrage about your recent comments about Haitians and Africans.

‘When neo-Nazis marched in Charlottesville, carrying torches and shouting about racial purity, you said they were good people.’ Photograph: Chet Strange/Getty Images

We could spend some time celebrating the fact that there’s still consensus about hating your blithering racism. But we’re far better off if we understand that you aren’t some alien invasion, even if your family were aliens from a country you were ashamed of until recently.

There’s a clear thread connecting your racism about immigration to historic racism in the country your family adopted as home.

One of your first executive actions in office was the Muslim travel ban. Perhaps your advisers haven’t told you this, but the courts certainly noticed that its racial and religious underpinnings run counter to the landmark 1965 Immigration and Nationality Act. That legislation overturned the racist attitudes that you share, enshrined into immigration laws in the 1920s which kept non-Aryans out of America.

Those 1920s laws did not happen by chance. They were shaped by supposedly expert testimony from advocates of the new pseudo-science of eugenics.

They were a singular achievement of the newly revived Ku Klux Klan, which found fresh converts by spewing hate about Jewish and Catholic immigrants even as it sought to revive the racist corpses of the confederacy. The Klan liked to say they were keeping America for Americans.

When he signed those immigration restrictions into law, President Calvin Coolidge said: “America must remain American.”

Sounds familiar? Ask your attorney general Jeff Sessions about that 1924 law, because he told one Steve Bannon (before he “lost his mind”) that America did really well after that eugenics-inspired law took hold. Then the country went downhill after the 1965 reforms. “We’re on a path to surge far past what the situation was in 1924,” Sessions told Bannon on his radio show in 2015.

No wonder you found it so hard to disavow the KKK during your presidential campaign.

Those who disavow Trump now are the only glimmers of hope. We salute you, Mia Love, the former rising star of the Republican party, who represents Utah in Congress and whose family has Haitian origins. “The president must apologise to both the American people and the nations he so wantonly maligned,” she declared.

Those who seek to justify or even celebrate Trump must face as much public disgust as the racist-in-chief himself. Yes, we’re looking at you Tucker Carlson, Fox News host, who insists that Trump is just speaking truth to liberals. Or perhaps Tucker and friends still believe in the Donald Trump who said this to Haitian-American voters late in the presidential election: “Whether you vote for me or not, I really want to be your biggest champion.”

If this is what it looks like when Trump is their biggest champion, it’s time for Haitians to ask the president to stand down. They have surely suffered enough.

• Richard Wolffe is a Guardian columnist