Prepare for a population explosion that will make immigration even worse

Such are the mathematics of greater longevity in combination with falling fertility, that when it happens, it will be sudden and precipitous.

As the authors of a new study published in The Lancet last week point out, the implications are immense. “Future trends in fertility rates ... will completely reconfigure the global economy and the international balance of power”, says Natalia V. Bhattacharjee, co-author of the study, and a lead research scientist at the Institute for Health Metrics and Evaluation (IHME).

What is so interesting about projections like these is that they have very little to do with the mass extinction events and Mad Max-like dystopia of much science fiction, but are instead simply a natural consequence of growing prosperity and abundance. Destitution has nothing to do with it.

At the tail end of the 18th century, the Rev. Thomas Malthus propounded the idea that populations tend to expand until they outrun their food supply. Yet his fears that population growth might lead to starvation in the near future could not have been further from the truth; humans have been highly effective in expanding the supply of food to meet society’s growing needs. So much so that in high-income countries you are today far more likely to die prematurely of excess than deprivation.

The bottom line is that the more prosperous an economy becomes, the less it procreates. The reasons for this are complex and multifaceted: contraception, mass education, growing female participation in the workforce, urbanisation, decreased reliance on large families as a form of welfare, family breakdown, growing polygamy, self-centeredness and so on.

I come from a family of nine siblings – seven brothers and two sisters. Even when I was growing up, this was extremely unusual; people tended to think we were either Catholic or Irish or both.

But today it is virtually unheard of outside migrant families, the extraordinarily well-off and perversely, the extremely poor.

Not so in the developing world, which is where the latest research is at its most interesting in terms of its implications.

In the high-income world, we are experiencing a “baby bust”, such that three quarters of nations globally are forecast to fall below population replacement birth rates by mid-century.

For all kinds of reasons, not least cultural, this may be concerning, but it is also very probably manageable, and might even be seen as a good thing if you believe human pollutants are killing the natural world. AI and automation should in theory come to our rescue.

But at the same time, we have a “baby boom” going on in large parts of the developing world, and particularly sub-Saharan Africa. Eventually, they too will succumb to the same forces as already observed throughout the “rich” nations of the OECD, but it will take time, and for now, they face a veritable explosion in population.

Thanks to modern medicine, and therefore declining infant mortality rates, population growth in many of these countries may far outstrip anything seen in the West during the great leap forward of the industrial revolution, or later the catch-up nations of Southeast Asia.

This is in turn likely to greatly exceed their capacity to create jobs and opportunities in sufficient numbers to satisfy demand, and with growing pressures on land and resources may possibly lead to precisely the sort of eventual implosion warned of by Malthus.

It is perhaps this phenomenon where we should be focusing our attention, rather than on the declining fertility rates of more developed economies such as the UK.

Back in the high-income world, the obsession is with how we pay for a rising dependency rate – that is the growing proportion of economically inactive, elderly citizens. By fundamentally changing the demographic mix in the economy, the combination of rising longevity and falling fertility is already creating extreme fiscal challenges.

Policymakers have tended to lean mechanically and heavily for solutions on mass migration, but this is proving increasingly toxic politically, and in any case there are growing questions around its economic effectiveness.

When dependents are taken into account, some migrants may be as much of a cost to the exchequer as a contributor to it.

Furthermore, many of the relatively low income, low skilled roles they occupy are unlikely to contribute much to productivity growth, so won’t pay for themselves in enhanced economic potential.

The once presiding assumption that mass immigration is always economically beneficial looks increasingly questionable. If capturing only the highly skilled, then it works, but even the best immigration regimes struggle to achieve this aim.

Efforts to improve the fertility rate through family-friendly policy – sometimes in the name of cultural nationalism, as with socially conservative political leaders such as Vladimir Putin, Hungary’s Viktor Orban and Italy’s Giorgia Meloni – have historically made little or no difference.

Meanwhile, the pressures building at Europe’s and America’s borders grow ever stronger.

Leaving the European Convention on Human Rights might help at the margin when dealing with small boats and bogus asylum seekers, but it will struggle to hold back the incoming demographic tide from Africa, the sub-Continent and beyond.

The Office for National Statistics recently projected that the UK population would grow by a further 6.6 million over the next 12 years, overwhelmingly through migration. If you think the politically and socially destabilising effects of mass migration are already bad enough, you ain’t seen nothing yet.

Solutions? Without wishing to be fatuous on such an important matter, a really serious pandemic, such as the Black Death – which wiped out up to a third of Europe’s population – might just about do the trick. Then the whole world would be fighting for migrants.