The United States’ global preeminence owes a great deal to demographics. After the collapse and fragmenting of the Soviet Union, the United States became the world’s third most populous country, behind the giants China and India. By comparison to other developed countries, the United States maintained unusually high levels of fertility and immigration—a phenomenon I termed “American demographic exceptionalism” in these pages in 2019. Since the end of the Cold War, the overall American population and its number of working-age people (between the ages of 20 and 64) have grown more rapidly than those of other developed countries—and faster, too, than those of rivals China and Russia. Growing working-age populations boost national productivity in economies run by governments that can successfully develop and tap human resources. For modern welfare states, the slower aging of the population forestalls some of the fiscal burdens built into current arrangements.
To the extent that crude demographic trends matter in world affairs, they have been running to the United States’ advantage for some time. But big changes are underway. The initial returns from the U.S. 2020 census and the reports about last year’s birth totals offered sobering news: with the slowdown of population growth and steady declines in national fertility, the United States now seems to be charting a less optimistic demographic path, one leading to a grayer and less populous future.
The United States may be losing its advantage and becoming less exceptional as Americans choose to have fewer children. To the degree that lower birthrates signal diminished popular confidence about the future, the drop-off in fertility warrants attention and perhaps concern. Slower population growth could also have troublesome longer-term implications for Washington’s pay-as-you-go entitlements for senior citizens and other social welfare programs. But a look under the hood of the latest population data and projections suggests that there is no immediate reason to be alarmed about the country’s prospective international standing. The United States will remain in a strong demographic position with respect to its competitors for decades to come.
DECELERATION AND DECLINE
The U.S. Census Bureau’s 2020 “headline” numbers formally ratify something demographers already knew: the United States’ population growth has been decelerating steadily since 1990—and is now at the slowest recorded tempo in the country’s history, apart from the Great Depression era. Between 2010 and 2020, the U.S. population grew by an estimated 7.4 percent. That is a distinctly slower rate of growth than that of the previous decade, when the United States’ population grew by just under ten percent.
Interestingly—some would say surprisingly—immigration does not seem to have much to do with this slowdown: indirect indications suggest net immigration amounted to about a million people a year over the 2010s, roughly the same level as in the previous decade. Rather, changes in birth and death trends explain the shift. “Natural increase”—the total number of births minus deaths—averaged 1.7 million annually for the decade between 2000 and 2009 but just 1.2 million between 2010 and 2019. In 2019, the year before the COVID-19 pandemic struck, it fell below 900,000, the lowest annual sum on record since at least 1933, when the United States’ nationwide birth and death registration system was completed.
The United States will remain in a strong demographic position for decades to come.
The falloff in U.S. natural increase in the 2010s was partly due to an increase in annual deaths—an entirely predictable result of the aging of the overall population. But the slump in births played a greater role. Birth totals in 2019 were down by over half a million from their all-time high of 4.3 million in 2007, just before the Great Recession.
Total fertility rates—a measure of births per woman per lifetime—tell the American childbearing story on a more human scale. For the two decades leading up to the Great Recession, the United States’ total fertility rate averaged just over two births per woman. Between 2007 and 2019, however, the U.S. rate dropped from over 2.1 (just above the level for long-term population replacement) to 1.7, below replacement level. That was the lowest rate ever recorded for the United States—until now. The provisional birth figures for 2020 indicate another four percent drop, to about 3.6 million, implying a 2020 national total fertility rate of around 1.64—more than 20 percent below replacement level.
The available data document a substantial and remarkably widespread fertility reduction since the Great Recession. Demographers are wary of supplying definitive reasons for such changes. Economic concerns may play a part, with some blaming the high costs of child-rearing for their reluctance to have more children or any children at all. Younger generations may also have different priorities and cultural attitudes from those of their predecessors; the rising cohort of millennials, who make up most of today’s population of childbearing ages, is decidedly less religious and also less sanguine about the future.
AN ENDURING ADVANTAGE
But the demographic future remains relatively bright for the United States. The 2020 census results seem far from harbingers of doom, especially when placed in a broader context. Take, for instance, some of the low-end projections of future U.S. population growth. The UN Population Division’s “low variant” models are instructive: these assign the United States a total fertility rate below 1.4 for the second half of the 2020s—a nationwide average lower, in other words, than that of any single U.S. state in 2019—and an even lower rate during the 2030s and 2040s. Even with this strikingly low fertility rate, the projected U.S. population would still rise for the next generation, peaking in 2047 at just under 350 million people, where it would roughly remain through 2050. The number of working-age people would likewise rise modestly during the next quarter century in this scenario—to a projected 2050 level about five percent higher than the corresponding total for 2020.
As that exercise demonstrates, the 2020 census results should not cause a “depopulationist” panic. Even with extreme and unrelenting sub-replacement fertility levels, the United States’ total population and working-age population are on course to keep growing. Continuing migration and the “population momentum” built into the United States’ current demographic structure (as rising cohorts move into age groups currently occupied by comparatively smaller cohorts) would push the overall U.S. population and working-age population to higher totals for at least another generation.
As a result, the United States will likely retain a demographic edge over other great powers. China, Japan, Russia, and the countries of the European Union have all had sub-replacement fertility rates for much longer than the United States. Their current fertility levels are all lower than that of the United States. And their populations are all older than the U.S. population today. (China has the most youthful population of those other powers, but its median age has already exceeded that of the United States.)
The median age of China’s population has already exceeded that of the United States.
The United States’ most recent year of achieving replacement-level fertility was 2008. By contrast, Japan and the EU fell into sub-replacement fertility in the 1970s, China and Russia in the early 1990s. Although the United States’ surfeit of births over deaths has been steadily dwindling for over a decade, deaths have outnumbered births in the EU since about 2012, and Eurostat projects the combined population of the 27 EU member states will begin shrinking around 2025. Japan has had a surplus of deaths over births since 2007 and a continuously shrinking population since 2011. Russia has seen nearly 14 million more deaths than births since the fall of the Soviet Union.
As for China (as I noted in Foreign Affairs back in 2019 and again this year), the working-age population is already in decline; depopulation is set to commence within the coming decade—perhaps much sooner—and the country is on a path toward extremely rapid population aging, with all that implies for economic performance and domestic social need. The particulars of China’s future demographic course will become clearer when the details of China’s 2020 census are divulged—but Beijing’s unexplained month-long delay in announcing even summary findings from the count suggests official displeasure with those results. Among other unpleasant demographic surprises, the Chinese Communist Party has seen births plunge since the suspension of the regime’s harsh one-child policy in 2015. China’s still imperfect vital registration system tallied almost 18 million births in 2016, but the 2020 census reports only 12 million births in 2020. That extremely low reading may reflect the shock of the COVID-19 pandemic (a crisis the regime insists it has always had well under control)—but as demographers learn more, they may find that China’s demographic slide is progressing even more rapidly than they thought.
Of all the presumptive great powers, only India stands to see greater and more rapid total population and working-age population growth than the United States over the coming generation and to remain a more youthful society than the United States. As is well known, in just a few years India will displace China as the world’s most populous country and will surpass China in working-age population shortly after that. But India is now entering sub-replacement fertility, too: UN estimates suggest India’s under 20 population is already declining, and India’s working-age population could peak before 2050.
QUALITY, NOT JUST QUANTITY
The dip in fertility in the United States does suggest that clear-cut U.S. demographic exceptionalism may be over, at least for the time being. The United States will likely surrender its place as the third most populous country in the world to Nigeria at some point before 2050. But it will remain a fairly young and vital society, at least with respect to other developed countries and to competitors such as China and Russia.
Nevertheless, U.S. strategists and policymakers should not take too much comfort in this fact. Raw population numbers won’t on their own strengthen the United States in its competition with others. The United States must also maintain its edge over competitors in developing human capital—a lead that has been dwindling for decades. Revitalizing health, education, and other facets of the country’s human resource base is an urgent task in its own right—and will pay geopolitical dividends.
