How annoying it is when voters don't do what their demographic profile says they're supposed to do. The polls before the EU referendum said that ethnic minorities – just like the young and the university-educated – were very securely stationed in the Remain camp.

But the results from Thursday suggest that many of them, especially Asians, may have defied the script when they actually entered the polling booth. Just like white voters in Labour's post-industrial heartlands of the North and the Midlands, they seem to have been moved by the issue of immigration and provided the decisive boost that propelled Leave over the finish line in first place.

There is not yet official data to confirm this view, but the evidence is there in results across the country. Places like Bradford, Oldham and Rochdale in the North could not have come out so clearly in favour of Brexit without a very significant slice of votes from Asians.

The same is true of Birmingham, Derby and Wolverhampton in the Midlands and Luton, Slough and Hillingdon in the South. My own anecdotal evidence from Asian family friends in the Midlands uncovered – what is to my mind – a shocking echo of the anti-immigrant rhetoric spouted by Leave campaigners.

I say shocking because it did not appear to be based on any direct negative experience of life alongside Eastern Europeans. These are not people who have lost out on jobs or seen their wages depressed by recent immigrants, and they are not struggling to access scarce public resources as they usually pay for such services privately.

Rather, their views were based on nothing more than base and irrational prejudice. It was exactly the same sort of unthinking xenophobia and – occasionally – outright racism that was routinely hurled at us Asians up until a couple of decades ago. Some of the language I heard would have felt very much at home at a BNP rally.

Bizarrely, it was accompanied by a belief that leaving the EU would lead to a more favourable immigration regime for those from India and Pakistan. Indeed, this was precisely the promise peddled by the employment minister Priti Patel as she toured Asian communities to drum up support for Brexit.

It takes only a cursory glance back at the poisonous nature of parts of the Leave campaign to realise this is an utterly forlorn hope. What began as a reasonable argument about immigrant numbers eventually morphed into a sinister appeal to the dark forces that lie in the deep recesses of the human psyche. Hatred and fear were whipped up as a wildly exaggerated and often bogus link was drawn between foreigners – any foreigners, whether they be from Poland, Turkey, Albania or even Syria – and membership of the EU.

This exploitation of the primal human fear of the 'other' is possible in any society at any time, but mainstream politicians – from which I exclude the likes of Nigel Farage – are usually responsible enough not to indulge in such tactics. Not on this occasion though. And it worked. I have no doubt it was the ultimate cause of Leave's victory, the difference between scoring 52% and, say, 48%.

Brexit Nigel Farage
Leader of the United Kingdom Independence Party (Ukip), Nigel Farage speaks during a press conference near the Houses of Parliament in central London Glyn Kirk/ AFP

It was so effective that it even turned sizeable numbers of Asian immigrants against those now following them to Britain in search of a better life. And, worryingly, its main legacy may be to legitimise and normalise such tactics as a valid part of mainstream politics. It succeeded once, so politicians will not be afraid to tap into such forces again. And next time they won't discriminate between apparently "good" and "bad" migrants.

Now that Eastern Europeans are out of the way, who can be demonised next in the scramble for votes? Muslims? Other Asians? African/Caribbeans? All are fair game in this sport. That is why so many pro-Remain Asians I spoke to after the referendum result expressed very deep concerns about the future place of all ethnic minorities in British political discourse – and indeed in wider society.

I am reminded of the famous poem about Nazi persecution by the German pastor Martin Niemoller, First They Came…. He began: "First they came for the Socialists and I did not speak out – because I was not a Socialist." He described how next they came for the trade unionists and the Jews with similar results, before ending: "Then they came for me – and there was no one left to speak for me."

To a certain degree, we may be in the midst of a culture where "first they came for the Poles and Latvians" progresses inexorably to "then they came for us". Those who were hypnotised by the allure of the anti-immigrant rhetoric are in danger of becoming its next victims.

This is not what was supposed to happen, however. Polling early on in the campaign by the British Election Study showed that around two-thirds of Asians – like other ethnic minorities – were in favour of staying in the EU. But this came before the deliberate switch in the Leave campaign's tactics to a more overtly anti-immigrant message about a month prior to referendum day, after which attitudes could have changed.

A woman reads a newspaper on the underground in London with a 'vote remain' advert for the Brexit referendum Reuters

A poll conducted by Lord Ashcroft after the referendum again found that around two-thirds of Asians said they voted Remain. But his sample of 12,000 voters could not have included more than a few hundred Asians, who may not be too representative of what happened across the community. Voting results, especially in the Midlands and North, suggest a higher proportion must have favoured Leave, which also tallies with my own (admittedly very anecdotal) experience.

The bitter nature of the referendum campaign has exposed and exacerbated deep divisions in the UK – between England and Scotland, young and old, the metropolitan elites and provincial working classes. Alongside these splits, many members of the nation's ethnic minority communities are left worrying about their futures after so many hateful sentiments were expressed without fear of recrimination during the last few weeks. I suspect we can all live with the economic and practical consequences of Brexit, but not with the unseemly means by which the vote was won – if they become a marker for future electioneering.

Senior Tories like Michael Gove and Boris Johnson – and their cheerleaders in the right-wing press – unleashed a wild and destructive beast when they consciously allied themselves with the tactics of Ukip. As the custodians of post-referendum Britain, it is incumbent upon them to push the beast back into its cage and to keep it there. Otherwise, this country will rapidly become a far less pleasant place to live.