Matthew Goodwin is professor of politics at the University of Kent. He is the co-author of National Populism: The Revolt Against Liberal Democracy (Penguin)

The global debate about populism has gone terribly wrong. It has become utterly obsessed with impoverished “left-behind workers” while ignoring the group that really matters: middle-class elites.

This is the thesis laid out in the Financial Times this week by Simon Kuper. What Trump, Brexit and Salvini have in common is not that they represent a backlash among the economically left behind but that they signal the “revenge of the middle-class anti-elitist”.

And who is this middle-class anti-elitist? Well, according to Kuper, he (most populist voters are men) is part of the “comfortably well off”. He owns his home. He lives on an “above-average income”. He lives not in a left-behind town in northern England where the factories shut but in the more prosperous southeast, which enjoys countless economic advantages. He is, in short, comfortably middle-class. All of this leads Kuper to ask what he thinks is the key question: why do well-off people vote against the system?

This is an interesting question but if you are trying to understand the current populist moment then it is the one wrong one to ask. It is also a question that reveals a lot about where people go wrong in the wider debate. Let me explain why.

To back up his thesis about middle-class populist elites, Kuper, like many others, points to the findings that two-thirds of Trump voters in 2016 lived in households that enjoyed above average incomes while “[m]ost British Leave voters lived in the south of England, and 59 per cent were middle class”.

Kuper is by no means the first person to try and make this point. In his description of middle-class elites, he approvingly cites the work of Danny Dorling, a geographer at Oxford University. Like Kuper, Dorling argued that Brexit is “unfairly blamed on the working class in the north of England” while “most people who voted Leave lived in the south of England”. These are interesting points but they are also very misleading points.

Let’s start with geography. As the academic Chris Hanretty, pointed out a while ago, such arguments suffer from basic statistical errors. If you take the absolute number of voters then there are more Leavers in the south of England than in the north — but this is because there are simply more people living in the South full stop. If, instead, you look at the proportion of registered voters across these regions then 39 per cent of people in the north voted for Brexit compared to 36 percent in the South. I’m not sure about you but I found it remarkable that somebody had to point this out.

Populism isn't about class By Matthew Goodwin

Nor are Kuper and Dorling the only ones to make the error. Writing in the shadow of the referendum, Guardian columnist Zoe Williams urged us to challenge the conventional wisdom that left behind northerners played a central role in the vote for Brexit. “Think the north and the poor caused Brexit? Think again.” Much like others, Williams contended that “most Leave voters were in the south: the south-east, south-west — indeed the entire south apart from London voted leave”. And “most leave voters are middle class”.

I do not need to reiterate why the geographical story is misleading, although it is worth noting additional analysis by Hanretty which hammers home the point. If you exclude votes from the regions that he includes in the south then we are left with 11,659,834 votes for Leave and 9,982,985 votes for Remain. In other words: “Leave wins whether or not you include the South”.

For writers on the liberal-Left, the idea that political outcomes they dislike are really driven by southern Right-wing Tories who they also happen to dislike must be incredibly seductive. It also happens to fit well with the old Marxist trope of prosperous elites colluding to defend their resources from the downtrodden workers below who could not possibly want things like Brexit or President Trump! False consciousness is back with a vengeance, or so we are told.

The problem is that it is just not convincing. To see why let’s move past geography to look at income and class. For Kuper, populism in the developed world “is less a working-class revolt than a middle-class civil war”. Many Trump voters, we are told, enjoy comfortable household incomes of at least $50,000 per year while most of Britain’s Leavers, as Williams and Dorling also argued, were really part of a hacked-off middle-class. Is it true?

Populism isn't about class By Matthew Goodwin

Not really. To begin with, the reason why most Brexit voters are middle-class is because … most voters are middle-class! As others point out, because middle-class voters represent such a large proportion of total voters it is entirely possible for most Leavers to be middle-class, even if most middle-class voters opted to Remain in the EU. Meanwhile, within that context it should be remembered that large majorities of working-class voters openly said that they voted Leave — 59 percent according to the National Centre for Social Research, or 63 percent according to Ipsos-MORI.

But what about all of those affluent Trump voters in the US? Well, this is the bit where a large pile of evidence on the Trump vote is completely ignored. As Roger Eatwell and I outlined in our book National Populism, almost of all of this work shows, conclusively, that when you are trying to explain what drives support for Trump income does not really matter at all. It rarely has any significant statistical effect.

For example, in his comprehensive review of almost every study of the Trump vote, the political scientist Matt Grossman concluded that objective characteristics like income really do not make much of a difference while another scholar, Diana Mutz, similarly found that people’s financial well-being was insignificant in explaining why people opted for Trump.

If anything, it is feeling economically left behind — not affluent — that appears to have an indirect effect. As we showed in our study of the Brexit vote, for a significant part of the Leave electorate feeling left behind made them less likely to see Brexit as a risky endeavour, which in turn cleared the way for them to vote to Leave the EU. But this is very different from the claim that income has a direct effect while these voters are certainly not “comfortably well-off”.

And what about Kuper’s “middle-classness of populism”? Again, the empirical reality looks rather different. As countless studies have shown, one of the reasons why national populists are thriving right now is because they have forged a very strong connection with the working class, in particular manual workers. Some have also eaten into the low skilled service sector. Very few thrive among the golf-playing, middle-class suburban elite that Kuper highlights.

Populism isn't about class By Douglas Murray

But even then, take another step back and you’ll see an even bigger problem. If you really want to predict whether or not somebody votes for populists then, actually, knowing their income or class does not take you very far at all. What really matters, much more so, are their attituded toward issues like immigration and the EU, which, in turn, reflect their underlying values. Across Europe, it is opposition to immigration that consistently emerges as the most significant predictor of support for populism, which in turn reflects the social conservatism that unites these voters. Part of this, but not all of it, is in turn shaped by educational experiences.

What unites the wealthy Trump voter in New York with the left behind worker in Kentucky is not middle-class elitism but a set of values that make them suspicious of social liberalism, opposed to mass immigration, desiring of stability and order and respectful of the traditional family and traditional values.

Kuper is certainly right to point to the need for a more nuanced debate over the roots of populism; we do need to recognise the diversity that exists within these electorates. But focusing heavily on middle-class elites is not the best way forward.

Instead of re-hashing old debates about things like income, which academics settled in the 1990s, it would make much more sense to cultivate a more nuanced discussion about the role of values and cultural insecurity in driving political change.

We do not tend to hear much about these things in highly liberal papers like the Financial Times. This is largely because liberals are not very good at talking about drivers that do not involve material concerns like income or GDP. But the evidence is clear: if they really want to tackle populism then this is where they should start.

Matthew Goodwin is co-author of National Populism: The Revolt Against Liberal Democracy (Penguin Pelican)