British political debate has long been dominated by public anxiety about rising levels of immigration. How might that change if the population tide were to turn? Not at all, would appear to be the answer. Net migration has in fact been falling since before Labour came to power last July, and yet there has been no end of demand for ever tighter controls and no end of government acquiescence.

New figures published this week by the Office for National Statistics (ONS), adjusting historical data for methodological changes, show that net migration was 944,000 for the year ending March 2023 – about 40,000 higher than had previously been thought. The drop since then has also been steeper. The number for the year ending December 2024 is now thought to be 345,000 – lower than the earlier count by 86,000.

The fact that the initial figures were wrong raises difficult questions for the ONS. Ministers making policy should have access to reliable data. Political arguments should be predicated on numbers that voters can trust. But even before revision, the downward trend in data was clear. Net migration spiked in 2022, in part because of population flows connected to the easing of pandemic restrictions, but also because Britain welcomed large numbers of people seeking sanctuary from the Ukraine war and fleeing Chinese repression in Hong Kong.

These were one-off events. Meanwhile, the systematic tightening of visa conditions has, as intended, limited the volume of arrivals. The number of people leaving the UK has grown – mostly recent immigrants returning to their countries of origin, plus longer-established nationals emigrating. If these trends continue as expected, the net figure will keep coming down.

Recent analysis by the thinktank UK in a Changing Europe forecasts a drop to between 70,000 and 170,000 in 2026. That is still a positive sum and unacceptable to radical rightwing parties that demand zero immigration and the removal of people already settled in Britain. And while such rhetoric is encroaching into mainstream politics, the practical implications of such an extreme agenda – the brutality of forced expulsions, the violence inflicted on Britain’s social fabric, the economic sabotage involved in wilfully shrinking the labour force – would not be palatable to the vast majority of people.

Even a less drastic change, with migration patterns simply following the current trajectory, involves significant consequences that are not being addressed. Provision of social care, already a struggling sector, faces a mounting recruitment crisis in the absence of migrant workers. Without a steady supply of overseas students, many universities, already with precarious finances, will be pushed over the brink. Migration tends to boost the proportion of working-age adults in the labour market. As that ratio changes, growth is harder to achieve and Treasury revenues shrink, with painful fiscal consequences.

None of these forces has shaped political debate in the run-up to the budget. Instead, the Home Office has announced another set of measures designed to signal ever more ferocious intent to control the nation’s borders.

The government’s immigration policy has been devised to placate – and, all too often, to mimic – the irate chorus that fulminates against perceived inundation by foreigners. That attitude would be cowardly and shortsighted even if net migration were not falling. That it continues as the numbers decline reveals a worrying political monomania increasingly detached from economic reality.

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