Humanity has a variety of short-term problems and long-term problems. The latter are typically harder to address, because the harms manifest so slowly. By the time things get severe enough to cause a popular outcry, the underlying causes may have become entrenched. Unlike the proverbial frog in a boiling pot of water, it’s hard for humanity to just jump out once things get hot enough.
The long-term problem that people usually talk about is climate change, and that’s certainly worth worrying about. Fortunately, with the advent of cheap green energy, we now have the means to address that problem. But there’s another challenge that’s slowly creeping up on the human race, which we don’t have a good answer to: population aging and decline.
The U.S. used to be an outlier in terms of fertility rates. But since 2008, its rate has fallen by almost a quarter — due largely to shrinking fertility among Hispanic Americans — and now stands well below the rate of 2.1 required for long-term population stability:
Because of this, the optimistic population projections of earlier decades have abruptly evaporated:
Large-scale immigration is now the only way that the U.S. can sustain its population over the long term:
But after the next two or three decades, where will the immigrants come from? The whole world is experiencing the same trend. Over the last decade, Asia — where the bulk of the human population currently lives — has seen a big decline in fertility, while Latin America has seen continued declines. Both are now below the replacement rate:
Religion has proven no barrier to this. The most devoutly Islamic countries of the Middle East, North Africa, and Central Asia have all seen huge fertility declines.
Africa is the last bastion of above-replacement fertility on planet Earth. But even there, fertility is falling faster than anyone expected, dropping to 4.1:
Some forecasters even predict that the continent’s population will peak in less than four decades. Even if the rest of the world is willing to take in very large numbers of African immigrants (doubtful given recent political shifts), Africa is not going to ride to humanity’s demographic rescue for very long.
And to make things worse, the trend toward lower fertility rates doesn’t seem to have any bottom. In past decades, many demographers assumed that family size would fall to around 1.4 to 1.6 children and then stay there indefinitely, or even recover a bit. But in recent years, fertility in China and South Korea has crashed to levels once thought to be unimaginably low:
As things stand today, no one on the entire planet knows how to stop this trend.
In response to the looming global shrinkage of the human race, some people choose to simply shrug their shoulders and say things like “I’m fine with a less crowded country”. But this is like responding to climate change by saying you enjoy warm weather. There are plenty of reasons why an aging, shrinking population is a threat to the living standards that we currently, and to ignore these is simply to bury your head in the sand.
