Raising Fertility without Raising Nuclear Risks
It's not as straightforward as you think.
You might expect international security experts to have a lot to say about declining fertility. Not so, however. I’m aware of only one scholar and one large-N study that focuses on the relationship between fertility (or its correlate, demographic aging) and international conflict. The scholar—Mark Haas of Duquesne University—also has a monograph under contract, but it’s been listed on his website as “forthcoming” for several years.
This is deeply puzzling. Population is a key contributing factor in every credible measure of national power. States need young people to fight wars, and we’re already seeing in Russia what a demographic crisis can do to a state’s behavior and in Ukraine what it means for a state’s coercive capacity. Governments around the world are adopting costly pro-natalist policies, often with an explicit national security motivation. Academics across the social sciences are taking fertility seriously, but not in international politics.
What makes the silence of security scholars all the more interesting is that, unlike the literature in economics, for example, security studies doesn’t have a uniformly negative view of declining fertility. Haas’s first paper on the subject argues that demographic aging is likely to bring about a “geriatric peace” between the great powers marked by lower military spending as states devote a greater share of their resources to paying for people’s health care and retirement. Better yet, because the decline in fertility is affecting the United States the least of all the great powers, we should expect the United States to become more powerful relative to its competitors, which should reduce the risk of an attempted challenge against U.S. hegemony. If wars happen when a challenger believes that it’s powerful enough to displace the hegemon or revise the rules of the international order in its favor, then a more stable distribution of power should mean a more peaceful world.
The scholarly consensus, insofar as there is one, is a bit less optimistic, but we should still think that in the long term an aging population is basically a good thing for peace. Demographic crises tend to make states more aggressive in the short term, especially if a more powerful state is declining relative to a less powerful competitor (say, if China’s low fertility causes it to fall behind India, and India thinks it’s relatively powerful enough to challenge Chinese border claims) or if a state is worried that its own power is declining and its “window” for claiming territory or revising the international order is closing (if China believed that its power was peaking and it was either now or never to grab Taiwan).
Those types of crises are temporary, however. Once the period of demographic transition has passed, aged societies tend to fight fewer wars, since they have fewer financial resources and less manpower to draw upon to support military aggression, and their populations have more pacific foreign policy preferences than younger societies. Haas and several co-authors actually modeled the data on this, and they found that younger and more fertile societies tend to go to war more often, controlling for other variables like GDP per capita. (The y-axis here is the probability that a dyad goes to war in a particular year.)
These findings, albethey part of a small literature, should give us some reason to doubt claims that raising birth rates is an important lever for reducing existential risk. Will MacAskill suggests that it’s important to raise fertility if we want to train new researchers and develop technologies to address catastrophic risks like climate change and unaligned AI.1 But it’s unclear why we can’t simply rely on AI or increase the percentage of the population that works in research to avoid economic stagnation. And we have at least two countervailing reasons to think that, in many or all cases, more births mean more risk from great power conflict.
In the long term, higher fertility increases states’ capacity to invest in their militaries and fight wars. It also shifts the balance of domestic political power in favor of younger people, who have more aggressive foreign policy preferences than the aged.
Changes in fertility that favor secondary great powers relative to the hegemon increase the chance that a rising challenger will contest the rules of the international order and get into a war with the hegemon.
Even if you think near-term—and I mean very near-term—existential risk should be our most important consideration, raising fertility still doesn’t look prima facie like a good idea. You might think that we could raise fertility now and avoid the transitionary period when states’ aging populations begin to affect the distribution of power. That might have worked a few decades ago. But we’re already going through the transitionary period. If we raised birth rates starting today (well, nine months from today), more people wouldn’t start joining the labor force until almost two decades from now. At that point, the transitionary period would already be over, and a new baby boom would only raise conflict risks by increasing available resources for military spending and shifting the distribution of power again.
Now, there are still some very good reasons that we should want people to have more kids. Even if you get the ick from MacAskill’s argument and you don’t think about humanity in instrumental terms, you probably think it’s a good thing to bring people into the world who are going to live good lives—something that’s true of almost everyone in the West and even most people in the developing world. The most popular objection to this argument follows the form: “It reminds me, a progressive journalist, of eugenics, and I think anything that resembles or smells like eugenics is literally genocidal racism,” and that’s a really bad reason to be against more births! There are some non-crazy arguments, too—arranged here from most to least convincing according to me, a non-philosopher—including that most human lives are, on net, worse for animals than they are good for us; it’s good to make people happy, but not necessarily good to make happy people; and the absence of suffering is good, but the absence of pleasure isn’t bad. (Connor Jennings wrote a solid explanation and rebuttal of the latter view a few days ago.)
If you’re like me and you think these arguments are all either bad or mistaken, then you probably want to figure out the best possible way to improve the birth rate, which means balancing the good of higher fertility with the bad of conflict risk.
Unfortunately, the first mechanism by which fertility increases the chance of conflict is going to obtain basically no matter how you go about increasing fertility; more births are going to mean more investment in military technology, unless humanity reaches a point where it moves beyond war and the nation-states system.
But the second mechanism depends on where births are happening. If you increase fertility in the hegemon, you don’t risk upsetting international order. If you increase fertility in any other state that might challenge the hegemon’s authority, you increase the risk of great power war.
There’s disagreement among experts as to whether we should expect China or the United States to be more powerful after the next few decades. I tend to be partial to those who are skeptical of China’s ability to catch up and remake the international order, so I think it would be a good thing to encourage births in the United States and a bad thing to encourage births in China. But I give that view low credence, and I think there’s a reasonable case for increasing births in China but not the United States. (Although there’s also the risk that, if we prefer China, we increase catastrophic risks posed by stable totalitarianism.)
Whichever you choose, you have to think that the ideal situation is for births to occur in one country but not the other. That’s exactly the type of answer that gets you called a eugenicist by progressive journalists. But if you think nuclear war is a bad thing, that’s just a bullet you’re going to have to bite.
Coming back to this one often.
I spent one hour reading why saving a drowning person is bad because they might not be vegan,thanks