For anyone who’s stood on a packed train lately, the idea that Britain faces a population crisis might seem absurd. But the platform crush belies a demographic crash, little noticed when England and Wales recently posted its lowest birth rate figures – of 1.7 babies per woman – since records began.

We may hold our nose when nativists like Viktor Orbán describe his nationalisation of IVF clinics as a “strategic investment”, but across Europe tax breaks and cash handouts are everywhere and growing. This month Greece became the latest with plans for a €2,000 baby bonus, joining a long list of European countries now providing strong incentives for its people to have more children.

Indeed many demographers view Britain as oddly unsupportive of natalism, and of 41 OECD countries, the UK comes in 34th in paid parental leave. While in France mothers receive extra-long maternity leave and a cash bonus after their third child, and there are travel perks and reduced income tax for large families, in Britain child benefit is means tested and capped at two children. Oh Mon Dieu!

Former Eastern Bloc countries, once the family’s enemy, are now resurrecting the idea that parents must somehow be allowed to capture the economic rents of child-rearing. An outflow of young workers to the West, empty cradles at home and a reluctance to embrace immigration have produced an existential crisis.

Will Britain join the European baby push? By Paul Morland

From the Baltic to the Black Sea, governments are thinking long-term demographic thoughts. Hungary, which now spends four times more on pro-natalist measures than it does on defence, aims to get the birth rate up to replacement level — 2.1 babies per mother — by 2030.

Britain, too, has targets for the 2030s, but not for children. Indeed environmentalists behind our green carbon goals see population as a problem, even though — with the number of Britons living alone recently hitting 8 million for the first time — rising consumption per capita will be one consequence.

The green argument against children is popular, and it’s not just Harry and Meghan who fret about their minuscule contribution to population growth. A YouGov survey in January found that of under 35s who do not want children, one in seven cite fears for the planet’s future as their motivation. A fifth of British women are childless, the third highest proportion in the developed world.

Yet where this is a genuine sacrifice, it may also be unnecessary. Many demographers say global population is a lagging indicator and should top-out by mid-century, falling sharply thereafter. In many developed countries it’s already in free fall.

In Finland last month the Finnish equivalent of the CBI demanded that the government starts to think about managing fertility as it might inflation or growth. Whereas those traditional economic indices are cyclical, Finland’s fertility rate looks terminal. In just a decade it has crashed from 1.9 to 1.3 children per woman, creating a “doom loop” of ever older pensioners supported by fewer workers. The young pay more tax to sustain the welfare state, which means less disposable income for homes and babies.

Breaking that cycle is the work of decades, and governments rarely think that far ahead. As Ross Douthat wrote in the New York Times: “It’s very hard to find a way to effectively place value on things like the creation of new workers 30 years from now. It’s just too long-term.”

So could this be a job for a prime minister whose personal contribution to the British birth rate may be at least three times the national average? Someone who — by signing off on HS2 — understands that some projects are a generation in the making and that, though we’ve left the EU, we could still have much to learn from the continentals?

If he has at least two terms in office, Boris will serve to see other countries grapple with demographic challenges, and might be surprised by what he sees. When Vladimir Putin gave his annual state of the union address last month he spent 20 minutes on constitutional reforms and twice as long on the need to remedy Russia’s birth-dearth. Here, as elsewhere, religion is increasingly invoked; in neighbouring Georgia, the birth rate jumped after the Orthodox Patriarch took to personally baptising babies.

China, having ditched its wicked one-child policy, is now in a panic about becoming the first country to get old before it gets rich. For now it seems to be trying gentle persuasion – a recent stamp to mark the year of the pig showed three piglets, taken as a sign of government approbation for bigger families – but draconian measures may not be far off, with reports from some provinces suggesting that it is getting harder to secure abortions and divorces.

But could Boris launch a British pro-natalism agenda, while staying true to his liberal roots and new northern electoral powerhouse?

Will Britain join the European baby push? By Mary Harrington

For a policy so mired in memories of dictators ordering women to breed for the fatherland, a new wave of demographers is stressing the liberal case for pro-natalism. The Left-leaning IPPR think-tank has addressed the “baby gap” — the difference between the number of children wanted by women and those they actually had — which is running at about 100,000 a year.

A Guardian survey in 2014 found a third of couples would have more children were they not so expensive; indeed if British women had all the babies they wanted, our birth rate would be above replacement level. In the US, which has seen huge falls in fertility in the past decade, 40% of women do not have all the children they wish.

When I interviewed the demography writer Jonathan V Last for a BBC documentary last year, he stressed how reproductive rights once meant the ability to control fertility downwards, something still true in parts of sub-Saharan Africa. But in the developed world a woman’s ability to achieve her stated fertility ambitions can be seen as a form of social justice and source of empowerment.

Nuanced pro-natalism might also allow Boris to spike nativist guns (if that is, you believe that relying on ever increasing numbers of migrant workers stokes populism). Best of all, pro-natalism could allow him to forge a connection with his Leave heartlands and further undermine Labour’s territorial claims there.

In his book, The Road to Somewhere, David Goodhart argued that Somewhere women had been ignored by a highly-educated elite of Anywhere careerists, who obsess about things like boardroom representation.

Will Britain join the European baby push? By Douglas Murray

Somewheres, according to data from the British Social Attitudes Survey, are much keener on a work-life balance and feel pressured into going back to work after having a baby. “Thanks,” wrote Goodhart, “to those Anywhere assumptions, Britain has evolved into one of the most family-unfriendly tax and benefit regimes in the developed world.”

It may even be possible to mobilise the cultural arguments for bigger families. There’s strong evidence to show that children do better with siblings and, other things being equal, are less prone to mental health issues and obesity.

This is not an easy sell, because it can annoy the parents of only children (a segment of the parenting public which has now climbed to almost half of all couples), but that doesn’t invalidate the argument. It may be true that the growth in what the media calls “snowflake culture” owes something to the rapid rise of the singleton whose rough edges are not worn down by abrasive contact with brothers or sisters. It’s certainly true that a future Britain — and it’s coming — where a large proportion of marriages involve an only child marrying an only child, will consolidate wealth and militate against social mobility (something especially damaging to the prospects of children from bigger BAME families).

So go on Boris, do it for Britain. Do it for those patriotic hard-working northern Leave voters who want to see that you’re really serious about change. Roll out free IVF for the youngsters of tomorrow. Give young people a chance to start the sort of families their parents enjoyed. The cost will be dwarfed by the billions you’re about to spend on social care for the elderly — and in future decades we’ll all be reaping the rewards.