Trump might have meant the Bronx, not Puerto Rico

That happened to me too. I arrived in Texas during the big oil crisis of 1973-74, when queues at gas stations were a mile long, and everybody’s nerves were on edge.

My car was overheating, and I asked the mechanic at the station to have a look at it while I waited for a fill-up. He refused, saying he was busy. When I complained about the rotten service, he said: “Boh, if you doan lahk it here, go back where y’all come from.”

You probably expect me to say I was traumatised for life and sought immediate counselling, but in those days no one knew that was the requisite reaction. Actually, I was delighted, as I am every time my stereotypes are confirmed.

At a guess, however, that Texan grease monkey wasn’t a privately educated Wharton alumnus. Had he acquired such credentials, surely he could have found a subtler putdown than pointing out his mark’s foreign origins?

Not necessarily, as proved by President Trump, who boasts just such an educational background. Justifiably irritated by the ‘Squad’, a group of four alternatively coloured congresswomen somewhat to the left of Jeremy Corbyn and easily matching his anti-Semitism, he told them to “go back and help fix the totally broken and crime-infested places from which they came”.

This was taken as a manifestation of racism. However, since the Squad leader, Alexandria Ocasio-Cortez (AOC), comes from the Bronx, Trump’s invective was even more apposite than it would have been even had he indeed referred to her family’s Puerto Rican origins.

The four women reflect the general leftward drift in Congress, a tendency corresponding to a similar development in Britain. There were left-wing congressmen during my time in the US (1973-1988), but I can’t recall anyone matching the febrile hatred of traditional America displayed by the Squad.

This animus goes beyond Trump, although they do see him as the personification of everything they detest. They are particularly incensed about Trump’s attempts to rid the US of illegal aliens.

AOC describes the detention centres at the Mexican border as “concentration camps”, Ilhan Omar talks about “mass deportations”, and Ayanna Pressley insists that: “We remain focused on holding him accountable to the laws of this land.”

One would think that fighting illegal immigration does uphold the law of the land, rather than violating it, but let’s not quibble about words. It’s the thought that counts, and especially the anomic hysteria behind the thought.

Most accounts of this incident talk about the Squad members’ obsession with identity politics and every conceivable socialist cause, or alternatively about Trump’s encoded appeal to his core electorate.

Not to repeat what others (notably Melanie Phillips in The Times) have said so well, I’d like to focus on something else: the nature of Americanism, and why variations on the theme of ‘go back where you come from’ are so popular in the US.

Since racial and ethnic particularism seems odd in a country of immigrants, it’s tempting to think of America as a nation in the grips of irrational racism and xenophobia. No doubt such sentiments exist, especially the former.

But I doubt that they, in their crystallised form, are much rifer than in some European countries I could mention. Racist and xenophobic language is definitely more widespread in some parts of the US than in Western Europe, but as often as not it masks something else.

Hence, for example, the joke: “What are the five most dreaded words in the English language? Hello, I’s your new neighbour.”

The serious concern reflected there has more to do with class than race. One is extremely unlikely to hear the sacramental phrase “there goes the neighbourhood” when a black doctor or lawyer buys a house in a middle-class area.

Middle-class ethos is the sun for which all Americans reach tropistically. Those who don’t share it are viewed with suspicion; those who attack it, with hostility.

Groups that sit above the middle class, and they do exist, keep themselves out of sight behind the walls of Newport mansions and the fences of the Hamptons estates. It’s the habitually downtrodden and their champions who are in plain view, and they are seen as somehow un-American.

In this connection it’s useful to remember that the congressional committee investigating the communist infiltration of American institutions back in the 1950s was called the House Un-American Activities Committee, not, say, the Anti-Communist Committee.

This wasn’t merely a euphemism, as is commonly believed. For communists were seen not just as ideological enemies of American democracy, but principally as ontological adversaries of American nationhood.

The country’s unique history is such that its nationhood is both more and less than just political, ethnic, linguistic and cultural commonality. Americanism is also, perhaps above all, an idea or even an ideology.

An American may be of foreign origin in the second or even first generation, but that doesn’t matter for as long as he unreservedly accepts the American idea.

This can be loosely described as unequivocal commitment to the liberties essential to achieving the middle-class American Dream of two cars in every pot and two chickens in every garage, or some such.

In that sense, it’s possible to become an American directly after stepping off the boat: all it takes is to feel the baptismal commitment in one’s heart. Conversely, in the absence of such commitment, even an American whose roots go back to the Mayflower may be perceived as an alien.

Trump is guilty of his customary savagery and characteristically slipshod research: he probably didn’t realise that three out of his four targets were born in America. But, perhaps inadvertently, he enunciated the essence of Americanism and the consequences of deviating from it.

In that sense he did appeal to his core electorate – not to their racism or xenophobia, but to their visceral understanding of what it is to be an American. They are, and the Squad really aren’t, regardless of where they were born.