In the long run, said John Maynard Keynes, we’re all dead, which perhaps explains why most of us worry much more about what’s happening tomorrow, or next week, than what might happen in ten years’ time, let alone in 50 years.

Yet sometimes we really should have to focus on what’s important, rather than what’s merely urgent; to consider the world that our grandchildren might live in; and to ponder our duty to them.

This is what Prime Minister Orban and the government of Hungary have done, through this conference. You’ve forced us to consider our countries’ place in the world, several decades hence, and what might best-be-done to keep us strong. Thank you.

In a recent interview, Prince Harry said that he and Meghan Markle intended to have no more than two children because of the human contribution to climate change. Like everyone, members of the royal family are entitled to have as few or as many children as they choose.

But having fewer children in Western countries will hardly make the climate better, given all the children that will be born elsewhere. It will, though, certainly make Western countries smaller and probably weaker too.

In a better world, which countries were large and which countries were strong would hardly matter. All countries would respect each other, and all governments would respect their citizens.

But in the real world, countries, like people, can’t help competing against each other; nearly always entertainingly in sport, mostly usefully in trade, and often destructively in geo-politics.

That’s why size matters. It doesn’t matter as much as strength, of course.

Israel, with just eight million people, has so far been quite successful at holding-off its much more populous neighbours, many of them bent on its destruction.

Still, without a buoyant economy, magnificent armed forces, and a population that’s totally committed to a flourishing Jewish state, on numerous occasions Israel would have been at the mercy of its numerically much larger opponents and its citizens could, quite literally, have been pushed into the sea.

Despite being the world’s most populous country, China was so poor and divided prior to 1949 that it suffered what it calls the “century of humiliation”.

Thanks to the relentless focus of its government and the market-reforms associated with Deng Xiaoping, China has lifted a half a billion of its people from the third world to the middle class in scarcely a generation. It’s the biggest advance in human well-being in all of history; and so far, that’s been pretty good for everyone else too.

But a richer China is also a stronger China, that’s rapidly changing the world’s balance of power through soft loans and through assertiveness in the South China Sea and elsewhere.

In 1960, China’s GDP per person was just one thirtieth that of the United States. Today, it’s about a sixth and rising fast. In 1960, Indonesia’s GDP per person was one sixtieth of the United States. Today, it’s one fifteenth.

Our problem, here in the West, is not so much that we’re getting smaller and poorer. It’s just that other countries are getting both bigger and richer faster than we are.

Overall, while most of the poorer countries have more people and more wealth than they did, most of the richer countries have relatively fewer people and are also relatively less well off.

In 1960, for instance, eight of the 20 most populous nations were in Europe. Today, just two of the top 20 largest countries are in Europe: they’re Russia, that’s dropped from the world’s fourth most populous nation to ninth; and Germany, that’s dropped from seventh to seventeenth.

In 1960, seven of world’s most economically developed (or OECD) counties were in the top 20 by population. Today, there are just three. In 1960, seven of the world’s top 20 by population were part of the Western alliance. Again, now, there’s just three.  

It’s undeniably good that more people in what were poorer countries are better off. But in the long run, it’s bound to change the global order. If the growing, rising countries are liberal pluralist democracies with a benign attitude to their neighbours and with a commitment to playing by the rules, all should be well and good.

But that’s hardly the case just now, and it’s unlikely to be the case for a long time to come; even if economic liberalism does eventually lead to a degree of political liberalism too.

And this shrinking of the West is only going to accelerate.

The UN predicts that in 2075, the United States will drop from the world’s third to fourth largest country by population with just over 400 million. By then, though, Nigeria will have nearly 600 million people, Pakistan nearly 400 million and Egypt and Bangladesh each about 200 million.

By then, the populations of Germany, Russia, Japan and Italy are predicted have declined very substantially; and in every Western country any population increase by then will be due entirely to immigration, invariably from what’s now the third world.

My country, Australia, is one of those tipped to rely entirely on migration for quite modest population growth. On current trends, and I stress current trends, and with very little migration, Hungary is tipped for population decline; that’s right, a decline to just seven and a half million by 2075.

Now, the better life that’s sought by the immigrants moving from poorer countries to richer ones usually includes the decencies and the freedoms that have long characterised the West. In Australia, an immigrant nation almost entirely, people have come to join us, not to change us.

But as the countries of Europe have discovered, a large enough migrant influx is hard to integrate and can put pressure on the character of long-established, long-settled societies.

So, on current trends, most Western countries could be expected to be somewhat different, as well as relatively and often-even-absolutely-smaller, and comparatively weaker 50 years hence.

As a former Australian prime minister, Paul Keating, once put it, the best migrants are our own children. It’s just that in Western countries, we’re not having very-many-of-them.

Now, Australia has always welcomed migrants so that we can fill more of our wide open spaces and thus more fully realise our potential as a nation. In Europe, though, immigration has been more a way to fill the jobs that there weren’t enough school leavers to do.

Hence the renewed interest in policies, especially here in Hungary, that encourage citizens to have larger families, rather than rely on immigration to keep populations growing.

Now, this has always been a policy interest of mine.

My first speech to the Australian parliament described middle-income-families-with-children as the “new poor” that needed more government support – support, I stress, that should never be characterised as “middle class welfare” but as a tax cut for families.

As party leader, I called for a comprehensive paid parental leave scheme that would make it easier for educated women-with-careers to do the most conservative thing of all, namely more readily to have children. Alas, our budget circumstances did not permit its introduction in government.

The John Howard government, in which I served, introduced a universal $5000 Baby Bonus.

It was subsequently means-tested and then effectively scrapped by the Labor government that followed, and – as well – it should never have been paid as a lump sum to welfare-dependent families, yet this policy was associated with a significant, if short-lived up-tick in the Australian fertility rate from 1.7 to 2.  

Here in Hungary, the Orban government has steadily ratcheted up support for families: with benefits through the tax system weighted towards larger families; home purchase grants and mortgage waivers for large families; a permanent tax holiday for four-time mothers; and even a car subsidy for larger families.

Some of these incentives have been linked to formal marriage, participation in work, and school attendance, so they’ve had a character-building as well as a family-supporting dimension.

Over the past decade, the fertility rate in Hungary has picked up from 1.2 to about 1.5. It’s not yet possible to say how much of this up-tick has been policy driven although it’s safe enough to assume that more support for families, especially traditional ones, will lead to more of them – because if you subsidise something you nearly always get more of it.

Hungary’s programme really does look unique – because it takes courage to defy political correctness enough to want to “go forth and multiply” – so it should be studied carefully by all other countries that retain a strong national survival instinct.

As another Australian prime minister, Malcolm Turnbull, once put it well: “the gravest threat to Western society….is neither global warming nor international terrorism. Rather it is the unprecedented, sustained decline in the birth rate….(so that) great cultures like Italy, Spain, Greece and Japan could become functionally extinct within a century”.

The real “extinction rebellion” should not be against our failure to reduce carbon dioxide emissions so much as our failure to produce more children.

The argument against policies to support larger families is always “why should my taxes support other people’s children”; to which the irrefutable response is “what if other people don’t have enough children to support you in your old age?”

I know that the last couple of generations, in economically advanced countries are the first in human history not-to-have-to-rely on the family for their social security. But having finally arrived at this place that all of our predecessors would have envied, why don’t we want more people, more of our own people, to enjoy these very best of times?

Or is it that with nothing much left to struggle for, there’s nothing much left to live for?

Our children are nearly always our most important legacy. Having children is a vote of faith in the future. Having more children would be the strongest possible expression of our faith that there really is a future worth living in.