Since the last few days of US political rhetoric will be studied by historians for some time, here a some snapshots from the past: In 1844, the city of Philadelphia was convulsed by race riots over three months, resulting in at least 20 deaths and requiring 1,000 troops to stop the violence.

In 1891, after a jury acquitted some of the defendants in a trial for the murder of a police officer, a mob of thousands stormed a New Orleans courtroom and shot dead 11 of them.

And in 1909, in Omaha, Nebraska, a young man was arrested while taking an English lesson from a woman. On the way to jail, he pulled out a gun and shot the officer who arrested him. Local politicians held a public meeting, whipping up a mob of at least 900 men who nearly lynched the gunman, then attacked and burnt down his neighbourhood, beating women and children and reportedly killing a boy. The entire community was driven out of the city.

Times columnist Matthew Parris has denied the US President is dabbling in racist politics (Picture: Chip Somodevilla/Getty)

These accounts sound like they belong to the hateful past of America’s Deep South, and slavery’s legacy of racism. But the communities targeted weren’t African American. In Philadelphia, it was Irish Catholics; in New Orleans, Italians; and in Omaha, the pogrom was aimed at Greeks.

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‘Anti-Greek hatred’ just looks strange written down. But one of Canada’s worst race riots took place in 1918, when anger at Greece’s official neutrality in WWI spilled out into the streets of Toronto. There were similar wartime riots in the Australian city of Perth, as well as outback mining towns. Of course, the point isn’t to make a comparison with the appalling, continuing toll of racism on visible, non-white communities – rather that whenever minorities and outsiders are told to go home, it opens the door to violence. The history of ‘go home’ rhetoric confirms: it’s profoundly racist and always has been.

And even when integration over generations brings violence to an end, bigotry survives for decades more. ‘No Greeks’ and ‘no Italians’ could be found outside boarding houses and in newspaper classified ads in the first half of the 20th Century, just like the ‘no blacks’ and ‘no Irish’ that lasted into the second half.

As a masters student in 1970s Montreal, my mother – born and raised in Canada as a third-generation immigrant – was told by professors not to study French because “this course is too difficult for a Greek girl”. Immigrants almost always start at the bottom of the economic ladder, with little or no power and influence. Historically, they were used as strikebreakers, often without their knowledge; today, they continue to be accused of taking housing and jobs away from established communities, driving down wages, and are vilified for their religion or held accountable for the actions of governments they leave behind – or even flee.

That’s why Times columnist Matthew Parris’ claim that President Trump’s comments would “strike a chord among millions who should not be called racists” is so wrong. He denied the US President was “dabbling in racist politics”, explaining: “There is such a thing as courtesy to a host country, even if it’s now theirs too. If in earlier centuries the many Irish and Italian (white) immigrants to the US had seemed to attack too fiercely and too early the beliefs and values of the country that had taken them or their parents in, they would have attracted irritation. ‘Why did they come there, then?’ is a question that, like it or not, would be asked.”

In a free, democratic society, participating in peaceful political debate is, in fact, a courtesy; and a place you live in – let alone somewhere you were born – ceases to become a ‘host’ once you call it your home. It is deeply sinister to talk about second and third generation immigrants as ‘guests’ – or even, as Parris wouldn’t but some do, ‘parasites’.

Why Matthew Parris is so wrong about Donald Trump’s ‘go home’ tweet – Paris Gourtsoyannis