Rarely can social scientists claim to be observing genuinely unprecedented phenomena.  In terms of demography, however, the world is, indeed, entering virgin territory:

• Europe and the Americas’ relative demographic decline contrasts starkly with the demographic ascendance of Asia and Africa;
• An escalating rift between aging affluent countries and youthful poor ones; and
• More people on the move than ever before

Hitherto, high birth rates had ensured predominantly young populations with few older people. War and epidemics, such as the plague, would intervene to depress population growth. By contrast, depressed population growth today is a function of a historically unprecedented decline in birth rates. That is, women are consistently having fewer or no children than at any previous time in history (for reasons that are beyond the scope of this research note). Differentials in fertility and mortality are not just affecting population structure.  Population structure affects political in/stability; and political in/stability is a catalyst for migration.  Demography in all its facets—fertility, net migration (immigrants-emigrants), mortality, population size, age structure, the first and second demographic transitions—is a vital ingredient in shaping the political process.  Its effect can be proximate or remote; first, second, or third order; necessary, but rarely sufficient; it can serve as a precipitant or a conditioning factor (Fischer & Hout 2006; Horowitz 1985, pp. 258–259).

In an age of demographic turbulence, the study of identity, institutions, and conflict cannot go forward without grasping how the key concepts and data on population change bear on problems in politics: “Demography must be considered a major driver of politics alongside classic materialist, idealist, and institutional perspectives. Just as no credible political scientist can afford to ignore the role of economic incentives, institutions, or culture, […] political scientists cannot afford to ignore demography in seeking to understand patterns of political identities, conflict, and change” (Kaufmann & Toft 2011, p. 3). This is better recognized in studies of long-term history, as when considering the role of demographic change in the origins of revolutions (Goldstone 1991), or in the rise and collapse of societies (Diamond 1997). Yet demographic factors also powerfully influence current geopolitics, fiscal politics, ethnic and religious conflicts, and voting patterns.

“Ten years ago, [demography] was hardly on the radar screen.  Today, it dominates almost any discussion of America’s long-term fiscal, economic, or foreign-policy direction” (Jackson, Howe et al. 2008, p. 17).  The next four decades will present unprecedented changes in long-term demographic trends, including the shrinkage of Europe’s labour force, the ex­treme aging of the advanced industrial societies, a global shift from mainly rural to mainly urban habitation, and a substantial turn in global economic growth toward the developing world (where 9 out of every 10 of the world’s children under 15 now live):

During periods when populations are growing fairly slowly, or when most societies have populations that are fairly homogenous and growing at a rea­sonably constant and steady fashion over time, these questions may not seem pressing for current politics. Yet we no longer live in such a world. The twenty-first century—following a century of global and regional intermixing borne by technological change and economic integration—is a time when diverse and rapid population shifts are taking place across the globe. Around the world, very young and very old age groups are increasing rapidly, and urban popula­tions are dramatically expanding. At the same time, migration and the political boundaries left from the ages of imperialism and colonialism have produced numerous multiethnic societies with shifting ethnic or religious composi­tions. In short, whether we look at issues of governance in the United States or the European Union, the impact of the BRIC nations (Brazil, Russia, India, China) on global economic and political affairs, or problems of governance and instability in Africa, the Middle East, Latin America, and Asia, the challenge of understanding the political impacts of demographic factors is inescapable (Goldstone 2011).

Demographic shifts caused by the uneven global demographic transition will intensify by the 2020s and continue up through 2050. Political effects will arise from growing demographic disparities between: (a) nation-states, e.g., a declining Russia versus a rising Pakistan; (b) age groups, e.g., the growing proportion of young versus old people in Afghanistan; (c) rural-urban groups, e.g., urbanization in the Middle East; and (d) ethnic or religious groups within states, e.g., Hindus versus Muslims in India, or evangelicals versus seculars in the United States.  Each form of demographic disparity is associated with distinct political conundrums: interstate changes in population size and age structure affect the global balance of power. Unbalanced age (and sex) ratios tend to alter rates of economic growth, unemployment, instability, and violence. Urbanization cre­ates dislocations that have traditionally been associated with religious, ethnic, class, or nationalist movements. And differentials in ethno-religious population growth may set the stage for ethnic, religious, and nationalist violence, value conflict, or challenges to the unity of what are often fragile states.

Two past presidents of the American Political Science Association, Robert Putnam and M. Kent Jennings, point to rapid demographic change as one of the most predictable future trends, yet one of the least studied by political scientists (Hochschild 2005, p. 314, 320).  In effect, demographers and political scientists live in parallel universes.  Demography is a recent science.  Belgian botanist and statistician Jean-Claude-Achille Guillard coined the term demography in 1855 to denote the scientific study of human populations in relation to the interplay brought about by changes in births, deaths and migration.  It began with English mathematician John Graunt’s observation of the underlying quantitative regularities in vital events.  His observations laid the foundation for the science subsequently styled “political arithmetick” by his friend Sir William Petty (1682).  Yet, preoccupation with the political implications of a population’s size actually dates back to the ancient Chinese, Greek and Arab civilizations (Dupâquier 1985; Spengler 1980, 1998). Demography, much like studies of economic behavior or social mobility, has evolved into a highly specialized and technical field, requiring advanced mathematics and the analysis of enormous amounts of data. The goal of this advanced work is to identify and plot the causes and patterns of population dynamics—that is, why and how populations change over time.

Yet, the consequences of demographic change are too important to be left solely to demographers. While demographers and their research are crucial to identifying the factors that produce various kinds of population change—from voluntary changes in behavior to patterns of nutrition and climate and disease—and to estimating how the current and future size and distribution of various populations and groups is likely to vary depending on those factors, demographers usually cannot tell us how people and social in­stitutions will react to those changes. That is the task of political demography. Fortunately it requires only a very basic understanding of key demographic concepts to grasp the various dimensions of population change. But such an understanding must then be coupled with a sophisticated and empirically sound understanding of political behaviour and social institutions to draw out the consequences of how various kinds of population change are likely to affect political relations.

Throughout history, the ebb and flow of population—through natural growth, epidemic diseases, and migration—has been linked to the rise and fall of empires, to conquests and revolutions. Periods during which populations were stable in size also tended to be politically quiet. By contrast, periods in which societies showed sustained growth, such as the century from 1550 to 1650, or from 1730 to 1850, were marked by severe political disruptions. Real wages fell and peas­ants faced shortages of land; social mobility and competition for elite positions increased as more surviving sons and daughters meant that simple inheritance no longer provided for stable succession; and state and urban administrations were stressed by the need to keep food supplies flowing and to enforce order among rapidly growing populations. As these trends persisted over several decades, the result was often rebellions, revolutions, and civil wars (Goldstone 1991; see also Ross 1927; Thompson 1930; Devaldés 1933; Bouthoul 1953; Sax 1955; Lorenz 1966; Ardrey 1966; Hutchinson 1967).

If demography matters for war, it matters just as much in shaping politics in peace. This is especially the case due to another long-term trend following World War II: the increasing democratization of states, including Eastern Europe, Latin America, and even more so, in Africa and Asia. Because de­mocracy has as its foundation the principle of majority rule, states adopting democratic forms of government will find themselves keenly interested in the proportions of the politically active groups that inhabit their territories (Toft 2003). Shifts in population composition can affect who wins and loses in political battles, leading to party realignments (Frey, 2011), or fueling violent conflict in fragile and transitional states (Goldstone 2002).

Whether looking at economic power or military capacity, population increase and decrease have always been identified as vital to a state’s security and war-making capabilities. Though identified as critical by classical thinkers such as Polybius, Cicero, and Ibn Khaldun, the importance of raw population as an increment of state power has waxed and waned over time, often in response to changes in the technology of war and the sources of military recruits (de Bliokh 1977; Mearsheimer 2001; Howe and Jackson, 2011).  For most of the last 200-odd years, since the work of Thomas Malthus, debates regarding population have focused on a single issue: will population growth and its effects (including pollution and consumption of natural resources) outrun the carrying capacity of local or global ecosystems, leading to wide­spread poverty? Or will technological progress outrun population increases, providing sufficient resources for continued income growth, so that only the distribution of resources is a valid concern? Although this debate continues today, it is remarkable that the discussion of how population affects political systems has persisted so long in terms of simple aggregates: the ratio of total population versus total amounts of resources.

This reductionism dates back to William Petty, Thomas Hobbes, Sir Walter Raleigh, Sir Edmund Spenser, and Sir Francis Walsingham (Spengler 1998).  One of the founding fathers of the United States of America, Thomas Jefferson, had already expressed concern about the relation between demographic density and civic life (1801; Smith 1999).  The preoccupation with the sterile notion of a population optimum, however, dates back to Confucius and Plato (Republic, Books II, IV, V; Laws Book V; see also Moreau 1949; Spengler 1980:200-201).  Confucius and his disciples posited a state’s population (Goy-Sterboul 1974) and its capacity to manage population growth (Huan-Chang 1911; Weber 1920) as its locus of power.  Given the ideal relationship between the number of inhabitants and the amount of arable land, they believed that there was an optimum (Chi-Chao 1930; Lee 1921).  Malthusian constraints emerge when the supply of labour incessantly outstrips demand and the technological advancement capable of sustaining economic growth and nourishing the population is sporadic (Coale & Hoover 1958; Meadows 1972): “The greatest test for human society as it confronts the twenty-first century is how to find effective global solutions in order to free the poorer three-quarters of humankind from the growing Malthusian trap of malnutrition, starvation, resource depletion, unrest, enforced migration, and armed conflict” (Kennedy 1993: 13).

But complex, multiple competitions for resources among popular groups, elites, and the state do not lend themselves to being conveniently simplified by theorizing, as with Malthus’s approach, about the overall balance of population and resources in a society.  To this end, Myron Weiner defined the field of political demography is defined as:

the study of the size, composition, and distribution of population in relation to both government and politics.  It is concerned with the political consequences of population change, especially the effects of population change on the demands made upon governments, on the performance of governments, and on the distribution of political power.  It also considers the political determinants of population change, especially the political causes of the movement of people, the relationship of various population configurations to the structures and functions of government, and the public policy directed at affecting the size, composition, and distribution of populations.  Finally, in the study of political demography it is not enough to know the facts and figures of populations – that is fertility, mortality, and migration rates; it is also necessary to consider the knowledge and attitudes that people have toward population issues (Weiner 1971:567, emphasis added).

To this definition Goldstone (2011) adds:

Political demography often begins by asking what the relationship is between the population of a society and its natural resource base and what the relevant trends are in the ratio of total population to overall resources. But that is just a basic starting point. Political demography goes on to study what changes in the distribution of resources and political power are likely to arise from changes in the absolute and relative sizes of various population subgroups: urban or rural populations; groups bearing various religious, regional, or ethnic identities; various elite groups or political factions; and different age groups.

Beginning with the American Civil War and continuing in World War I and World War II, the dominant role of machines in warfare made populations more vulnerable and at the same time less relevant to fighting power. Yet since the 1970s, population growth in developing countries, and the ability of major powers to put boots on the ground, have returned as key components of national security after a series of asymmetric wars in which high-tech, capital-intensive militaries lost bitter contests to less technologically advanced, labor-intensive militaries in Asia and Africa, such as the United States in Vietnam or the Soviet Union in Afghanistan (Arreguín-Toft, 2005). Moreover, political violence in the form of interstate wars between major industrialized powers—the type of conflict that had appeared to relegate people to insignificance from the 1880s to the 1940s—were superseded by civil wars.  Asymmetric warfare as exemplified in Iraq and Afghanistan places the accent on labour-intensive, longer-term counterinsurgency operations. As a result, a substantial military recruitment pool and a sufficient tax base to finance costly campaigns are again becoming vital to power projection. The demographic trends of the twenty-first cen­tury—aging great powers with shrinking labour forces alongside youthful and rapidly growing developing nations home to terrorism and turbulence—thus mark new challenges for geopolitical order.

The shifting nature of war and the so-called third wave of democratization are only part of the reason why demography is emerging as a critical issue in policy circles. Another is the demographic revolution that is sweeping across the globe. Unprecedented population aging in East Asia and Europe will see many developed countries’ over-60 populations approach 40 percent of the national total by 2050. This demographic development is historically without precedent; we do not know what to expect from a state with over one-third of its population over 60, nor how its economic growth and finances will be affected (see Howe and Jackson, 2011).    As many parts of the developing world transition through equally historic population booms, the strain on governments’ resources from national debt and the cost of aging populations has the potential to multiply systematically both the number of fragile states and the extent and depth of that fragility.  While Europe’s improved sani­tation and medical technology helped to cut infant mortality and generate a population explosion after 1750, the technical improvements were nowhere near as effective during the West’s (and Japan’s) population boom as they are today. The typical European population expanded three to five times during its demographic transition from 1750 to 1950, but today’s developing countries—which are benefitting from the latest medical technology—can expect to see their populations expand 8 to 24 times before their demographic transition runs its course (Skirbekk 2008).

In both population growth and age structure, the contrast between the rich and poor worlds is glaring. It could well lead to more con­flict between North and South over resources, migration and climate change, while making military interventions by developed countries more problematic.  Most of the world’s affluent coun­tries—in Europe, East Asia (Japan, South Korea, Taiwan, Singapore), and North America—have completed their demographic transition and have stable or very slow-growing populations.  Several of them, including Germany and many in Eastern Europe, have seen their Total Fertility Rate fall well below 2.0 children per woman, so that they are forecast to decline in population in the near future, save for consider­able in-migration.  By contrast, most of the world’s poorer countries—mainly in Africa, the Middle East, and southern and Southeast Asia—have only just begun their demographic transition, and so are continuing their rapid population growth.  Many countries in sub-Saharan Africa, again in unprecedented fashion, have seen their rates of fertility decline stall while mortality decline has accelerated; thus their demographic transition is entering a new phase of continued or even stronger population growth.

The young populations of the growing global South will strain at the seams of economies and infrastructure that are not only underdeveloped, but also de­signed for a much smaller population. This “youth bulge” is already having political repercussions. Youth bulges occur when there is an exceptionally large proportion of young people aged 15 to 29 among the adult population. The existence of a youth bulge—especially when it is dominated by unemployed young males—is associated with a higher incidence of violence and revolu­tion. Research indicates a low median age in the population may delay the onset of democracy, and may make democratic gains difficult to consolidate and maintain (Huntington 1996; Urdal, 2011; Cincotta & Doces, 2011).

In sum, no area of the world will be exempt from the impact of demographic change.  Rich countries are facing unprecedented aging.  Poor countries are facing large youth bulges and still-rapid growth.  In addition, all countries will be forced to deal with surging volumes of international migration as age and income imbalances drive people to seek work or to escape from local environmental crises or conflicts.

—

Christian Leuprecht is associate professor of political science at the Royal Military College of Canada and cross-appointed to the School of Policy Studies and Department of Political Studies at Queen’s University.  He is the author of a dozen books and 60 peer-reviewed articles and other publications on the strategic, political, economic, security and cultural implications of demographic change.

Jack A. Goldstone is Virginia E. and John T. Hazel, Jr. Professor and Director of the Center for Global Policy in the School of Public Policy at George Mason University, and a non-resident fellow at the Brookings Institution.  He is the author of Revolution and Rebellion in the Early Modern World, awarded the 1993 Distinguished Scholarly Research Award of the American Sociological Association; Why Europe? The Rise of the West in World History; and nine other books as well as over one hundred research articles on topics in politics, social movements, democratization, and long-term social change.  His latest book is Political Demography: How Population Changes are Reshaping International Security and National Politics (Oxford University Press, 2011).

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