Too Many or Too Few

One reason Thanos is an interesting and effective villain in Avengers: Infinity War is that he is not yet another stale “I want to rule the universe” psychopath in the vein of Ming the Merciless from the ‘30s Flash Gordon serials or Emperor Palpatine of Star Wars. Instead, Thanos is a cosmic eco-warrior. Even though his solution might give most of us pause, his basic concern (that there are too many people – defining “people” as all sentient beings) is widely shared among humans today. I’ve said as much myself (see my 2011 blog NPG [Negative Population Growth]) though I did not and would not suggest removing anyone already here.

When I was born the population of the USA was 150 million and the world population was about 2.5 billion. The US has more than doubled while the global population has more than tripled to 7.7 billion today. The global growth rate per decade has slowed from about 20% back then to 8.7% at present, but since there is a larger base today we are adding 67,000,000 people per year instead of 50,000,000 as in the 1950s. The increase overwhelms efforts to mitigate human impact on the environment. Yet, the ongoing rise is anything but uniform, and the variability indicates a way to reverse it: let poor countries grow rich. The well-to-do (or rapidly becoming well-to-do) countries of Europe, North America, and East Asia in the past few decades have seen their fertility rates drop through the floor to well below replacement level (2.1 per woman). In the 2000s the USA seemed to be an exception (almost) with a fertility rate hovering between 1.9 and 2.1, but in the 2010s the US rate dropped to a more typical first world level of 1.7 and shows every sign of dropping further. The one-child policy famously adopted by China in the late 70s apparently only sped up what would have happened anyway since fertility rates in Taiwan, Singapore, and Hong Kong are 1.13, 1.14, and 1.13 respectively. Several countries are already seeing absolute declines in population with Japan furthest along the path. Countries that are magnets for immigration (e.g. the US, UK, and Canada) still see and will continue to see in the next 30 years substantial population increases despite low domestic birthrates, though the demographic replacement that entails is not without social stresses.

A low birthrate in advanced countries has many consequences: a shrinking working-age population to support an expanding elderly one, for example. Life expectancy is increasing at the same time fertility is dropping; globally, the cohort over age 80 is the most rapidly growing segment of the over-65 population. One other limited but significant consequence is a reconfiguration of international power balances. Susan Yoshihara and Douglas A. Sylva address this in their book Population Decline and the Remaking of Great Power Politics. In their historical overview from ancient times to the late 20^th century they note that a growing population was seen by leaders as an unalloyed good – even in China as recently as the early 1970s. (Mao: Every stomach comes with two hands.)

Population and national power never have been and are not now one and the same. Economic, technological, political, and geographic factors matter, too: often they matter much more. Yet, population does matter; all else equal, the more populous nation does have a military advantage. Relative decline (e.g. China [fertility rate 1.6] vs. India [fertility rate 2.2]) can have profound effects. Russia, for example, retains a superb arms industry from small arms up to nuclear weapons, which ensures its great power status, yet its relative position can’t help but be undermined by it’s Western-style fertility rate (1.6) that is projected to reduce its population from 143 million to below 100 million in midcentury. It already relies on a tactical nuclear deterrent to defend itself in the Far East – as NATO did back when it was outnumbered by the Warsaw Pact. Russia is not alone. Say Yoshihara and Sylva, “the only European countries that will avoid population loss by 2050, according to UN projections, are France, the United Kingdom, Ireland, and Luxembourg, and even these countries will face rapidly aging populations.” The US by contrast, due mostly to immigration and to a smaller extent from longer lifespans, is expected to rise from 329 million today to 438 million by 2050, an increase larger than the entire US population in 1920 (106 million). This would seem to be a major advantage from a power-politics point of view, though of course economic troubles and/or political dysfunction could disrupt that. “The ‘demographic transition’ such as it is,” the authors warn, “will not lead to a demographic peace, nor will a ‘geriatric peace’ descend upon the powers in the next few decades.” The results instead could be turbulent, as relative changes on this scale have been in the past.

As that may be, there are benefits to a smaller population that (IMO) outweigh the risks and costs. There could be some curious outcomes. Since traditional and religious (e.g. Mormon) families tend to be larger (well over a 2.1 rate), for example, they may become a greater share of the population in time – unless their kids don’t follow the same path. It will take a few decades to know, and actuarial tables suggest I won’t be confirming that one first hand. It would be nice to see a global fertility rate drop below 2.1, however unlikely that might be in my lifetime. Thanos can snap his fingers in some other universe.

The Hollies – Too Many People: released 1965, the year the Baby Boom busted