The new Tory immigration system won’t work – except at the ballot box

There was a solitary question on the ballot paper in the 2016 referendum. It asked: “Should the United Kingdom remain a member of the European Union or leave the European Union?” The result – the majority vote to leave – was clear but close. Boris Johnson’s government has now begun to implement it and would like to pretend that the issue is done and dusted.

This is patently not the case. For one thing, most of the terms on which Brexit Britain will coexist alongside the EU remain to be decided. For another, it was common ground among leavers and remainers that a lot of umbilically linked questions clustered around the core EU argument. Among them were such things as austerity, business confidence, inequality, regional decline, hostility to London, nationalist narratives, resentment of elites – and immigration. Ever since 2016, these other Brexit-powered questions have helped to reshape British politics at least as much as Brexit itself has done.

The principal surrogate takeaway from the leave vote in the Conservative party has been immigration controls. Theresa May was a remainer. But she became Tory party leader in part because, as the former home secretary, she was identified with the strict immigration policy that leave voters were judged to be demanding in the referendum. May repeatedly made it clear that she saw border controls and curbs on migrant numbers as synonymous with the leave mandate. That baton has now passed to Johnson, whose post-Brexit immigration plans were published on Wednesday.

In this respect, Johnson is carrying on where May left off. He sees his immigration plan as second only to EU withdrawal itself in establishing the foundations of the post-Brexit Britain over which he wishes to preside. That’s partly why the policy has been announced while parliament is in recess. Headlines like the Mail’s “Immigration Revolution: Boris’s Border Blueprint” on Wednesday have had a perfect launch.

But it is important to be clear why Johnson, like May before him, thinks this way. It’s because, in the final analysis, the driving force behind this week’s new curbs is primarily political, not economic. It is as much about driving a wedge into the opposition parties as it is about achieving specific migration goals. It thus underscores a crucial change in the Tory party to which its rivals may not have yet adjusted.

Britain’s immigration debate has always been about both control and the appearance of control. In political terms, it is the appearance that counts most. That has been true ever since the 1960s, when the mantra of “firm but fair” immigration control as the precondition for domestic racial harmony and equality first took root. Johnson’s proposals this week, fleshing out the so-called points-based immigration system proposed in the party’s election manifesto, sit broadly within that tradition.

Nevertheless, the immigration issues that Britain faces in the 2020s are different in kind from those it faced in the 1960s. That is because the EU and EEA freedom of movement rights, which went with Britain’s 43 years of EU membership, are due to cease on 31 December. The large rise in EU freedom of movement after 2004 did more than anything else to drive up migrant numbers in the years before the referendum, even though it was the refugee crisis in Syria and north Africa that made the issue truly toxic in 2016.

Johnson’s plan is a political initiative masquerading as an economic one. Britain’s departure from the EU and its rejection of EU freedom of movement mean that new immigration rules are needed. But the governing approach in the new plan is to impress the voting public rather than to solve labour market issues that face businesses and domestic or overseas workers. The practical side takes second place to the message. Home secretary Priti Patel talked on Wednesday as though the new system would at last enfranchise 8 million UK workers to get the jobs that foreigners had been filling until now. This is total nonsense. The economically inactive are overwhelmingly students, retired or long-term sick. But it’s the immigration revolution headlines that matter.

The details of the Johnson-Patel package matter more to businesses than they do to ministers or the public. Sectors such as construction, where 14% of the existing labour force is said to be non-UK (the figure is 54% in London) face a real hit unless the boundary between skilled (good) and unskilled (bad) migrants is better managed than the government plan implies. The knock-on effect for Johnson’s ambitious infrastructure projects and hospital building pledges would be pretty dire if this does not happen. The hospitality industry will similarly be on an economic knife-edge, with destructive implications for the already struggling high street. There are likely to be many tweaks to this evolving plan once the news spotlight has moved elsewhere.

That is because these details pale into relative insignificance for the government when compared with the political dividends the Tories expect from the parade of tough action. Even though net migration has increased a lot in the past 20 years, public opinion routinely exaggerates its scale. It is likely to go on doing so as long as the Mail is around. The post-2016 fall in EU migration to the UK has made little difference. The polls consistently show that a majority (albeit a slowly declining one) want immigration cut. Everything Patel ever says shows that, however little she understands or cares about the detailed impact of this week’s plan, she absolutely gets that this is intended to be another “job done” moment for the government, just like Brexit itself.

The Johnson government’s approach to immigration is of a piece with its general approach to Brexit. The idea that the interests of business are the government’s priority, or that the modern Tory party can any longer be seen as the party of business, is largely for the birds. That internal battle was fought and lost in the Brexit battles of the last parliament. The Tory party has become a nationalist party, sustained by the tabloid press, rather than a class party sustained by traditional business interests.

Related: Immigration: firms will need to train more UK workers, says Priti Patel

The Tory party has also discovered, without necessarily intending to, something that centre-right parties and movements have simultaneously discovered in other parts of the world. Arguments based on national identity are proving to be tailor-made for splitting the social democratic constituencies that used to maintain parties like Labour. Social democracy’s working-class voters quite like the appeal to nationhood. Its middle-class voters, on the other hand, greatly dislike it. Putting these constituencies back together gets ever more difficult.

In Britain, Labour does not know how to respond on immigration – and Johnson knows it. One Labour response is to criticise his immigration plans for the problems they cause for business. Johnson does not care about that. He got where he is today by saying “fuck business”. Another response is to accuse him of racism. Johnson sees no threat there either. He reckons he will be laughing all the way to the ballot box as long as middle-class politicians accuse him – and his voters – of such things. His immigration plans may or may not work on the ground, in the high street or at the borders, but in the end that’s not the point. It’s not the economy, stupid. It’s the politics.

• Martin Kettle is a Guardian columnist