Cover: Demographics and the Changing National Security Environment

Demographics and the Changing National Security Environment

Published 2000

by Brian Nichiporuk

Research Brief

Demographic factors seldom directly cause conflict between nations. They can, however, exacerbate existing tensions and increase the risk of violent conflict. Long-term fertility trends, urbanization, migration, and changes in the ethnic composition and age profile of populations can influence the likelihood and nature of conflict among and within nations.

Brian Nichiporuk explores these issues in The Security Dynamics of Demographic Factors, seeking to answer three questions in particular. First, which demographic trends pose international security concerns? Second, what are the security implications of these trends? Third, what should the United States do in response to these issues? The future international security environment, of course, will be determined by complex interactions between geographical alignments, technological advances, economic developments, environmental trends, and demographic factors. This research does not address all these complex interactions, but it does note the directions in which demographic factors can affect security issues.

World population growth continues at a significant, albeit slowing, rate. Recent middle-range estimates indicate that global population could increase from 6 billion now to 7.3 billion in 2025 and 9.4 billion in 2050. Nearly all this growth will take place in the developing world.

Contributing to this growth are varying trends in fertility. States may be grouped roughly into one of three categories defined by economic development and fertility rates: developing states with continuing high fertility rates, developing states with declining fertility rates but continuing population growth, and developed states with fertility rates at or below those needed for population replacement. Urbanization continues apace in all types of states.

Two distinct types of fertility patterns currently contribute to population growth in the developing world. Some developing states, such as Nigeria (6.5 lifetime births per woman) and the Democratic Republic of the Congo (6.6 lifetime births per woman), continue to have high fertility rates. Such nations will continue to grow for at least two more generations. Other developing states, such as Brazil (2.5 total fertility rate), Mexico (3.1), Egypt (3.6), China (1.8), India (3.4), and Indonesia (2.7) have reduced their fertility rates but will continue to see population growth for at least another generation because of population momentum. Previously high fertility rates in these states have skewed the current population toward age cohorts in their childbearing years (see Figure 1 for a comparison of population age structures in developing and developed nations).

Figure 1. Developing Countries Have Younger Populations Than Do Developed Countries

Developed nations in Europe and East Asia face different challenges, those associated with low fertility rates, aging populations, and static population growth or decline. Most NATO allies of the United States have very low or negative population growth. Italy and Spain have some of the lowest fertility rates in the world, 1.2 lifetime births per woman. Germany is now experiencing negative population growth of –0.1 percent annually. Britain and France are experiencing very low growth, and Russia faces long-term population decline. In East Asia, Japan and Singapore face low growth. The United States is experiencing low growth rates, but not as low as those for some other developed countries because of a somewhat higher fertility rate and larger immigration flows.

While urbanization continues throughout the world (see Figure 2 on world urbanization trends), its security implications are probably greatest in developing states. High population growth in agricultural areas, subsequent soil depletion and deforestation, declining agricultural commodity prices, and perceptions that cities offer better economic opportunities have convinced more and more persons in rural areas to migrate to urban ones. One-half of the world population is now urban, compared to only 17 percent in 1950. By 2015 in the developing world, there will be 23 "megacities" with populations of at least 10 million residents.

Figure 2. Urbanization Is Proceeding Rapidly in the Developing World

Security Implications of Demographic Trends

Demographic trends have three kinds of security implications. First, they can lead to changes in the nature of conflict. Second, they can affect the nature of national power. Third, they may influence the sources of future conflict.

Changes in the nature of conflict. Changes in the nature of future conflicts are likely to follow from increasing urbanization, the spread of immigrant communities, and demographic pressures on renewable resources, such as water, as well as from independent changes in military strategy and technology. Future high-intensity conflict is more likely to take place in urban areas. This presents a particular challenge to the conventional warfare capability and doctrine of U.S. ground forces. The technological advantages that the United States enjoys in long-range precision weaponry might be reduced by the unique characteristics of urban warfare, including restrictions on movement and line of sight and the presence of civilians.

Urban areas are also more likely to be the site of future low-intensity conflict, particularly as they become even more important economic, political, and social centers. The rings of poor shantytowns that surround many Third World cities may be fertile recruiting grounds for radicals and revolutionaries fighting existing regimes.

Recent advances in transportation and communication have made intercontinental migration easier. This has increased the size, visibility, and impact of ethnic diasporas, especially in Western Europe. Within ethnic diasporas, activist groups can become a strategic asset for their home nations and territories. In extreme cases, rival diasporas might engage in violent conflict in their host countries to advance the causes of their home states.

Population pressures increase the likelihood that water rights will be a source of future conflict and make control of freshwater a more powerful instrument of coercion. This is particularly true in arid regions, where many developing countries are experiencing high population growth. Such nations are vulnerable to threats to their water supply during conflict, especially if much of their water comes from external sources.

Turkish control of the flow of Euphrates River water, for example, may become an instrument of coercion. The Grand Anatolia Project to build dams for hydroelectric power in Turkey will restrict the flow of Euphrates water to Syria by 40 percent and to Iraq by 80 percent. Completion of the project will also give Turkey the ability to cut off Syria and Iraq from all Euphrates water. Such power will loom large in any future conflicts between Turkey and Syria or Iraq over the political status of the Kurds.

Changing sources of national power. Demographic factors will compel both low-growth and high-growth states to develop different sources of national power.

Some low-growth states seek to base their military power more on capital and training and less on sheer manpower. Some states of Western Europe, for example, are moving away from large conscript armies designed for territorial defense and toward smaller professional forces tailored for expeditionary operations on the European periphery. Declining personnel levels free funds for the procurement of new and advanced weapon systems, whose operation requires a greater investment in each member of the military (e.g., for training and retention). Increasing weapon system costs will lead low-growth states to seek partnerships for sharing procurement costs to continue modernizing their militaries. Low-growth states that cannot otherwise afford to adopt a capital-intensive approach to warfare, such as Russia, may choose to rely more on weapons of mass destruction in their national security policies.

High-growth states, by contrast, may base more of their military strength on manpower. Many states with multiethnic populations see military conscription as a means to instill a common identity into the populace. Some need large numbers of military personnel to preserve order and protect against insurrection. Many developing states, to maintain their capabilities to prevail in conventional warfare against their neighbors, split their forces between elite units and low-quality infantry units. An example of this is the division of the Iraqi military into Republican Guard and regular army units.

Many other variables, such as geography, wealth, alliances, and threats and strategies to counter them, also contribute to differences in military forces used by different nations. Nevertheless, when all else is equal, differing population growth rates can lead to differing military force levels and mixes.

Changing sources of conflict. Demographic factors can cause conflicts. Massive population migrations, for example, contribute to instability in both home and host countries. The home country faces the risk that those departing will use the host nation to undermine the home state, while the host nation faces challenges ranging from an overburdened infrastructure to growing ethnic imbalances.

In some states, particularly those with a large number of unemployed young adults, high growth rates can lead to revolutionary movements. This is most clearly evident in the development of the Islamic Salvation Front in Algeria, which has a rapidly growing youth population and high structural unemployment. Successful revolutions in turn often lead to armed conflict, arising either from efforts by the revolutionary state to spread the revolution to adjacent states or because neighbors perceive the revolutionary state to be a threat.

Finally, demographic factors can lead to conflict in ethnically mixed states. This is particularly true in areas where ethnic groups are integrated rather than segregated into well-defined areas, where one or more of the groups have a nationalist history, where the groups have different growth rates, and where the central government is relatively weak. Bosnia in the early 1990s, as the Yugoslav central government was weakening, is an example of an ethnic conflict in which demographic factors played a role. Between 1961 and 1991, the Serbian percentage of the population in Bosnia declined from 43 percent to 31 percent, while the Muslim percentage of the population increased from 26 percent to 44 percent. This population shift accompanied the waning of Serbian dominance, and the increasing influence of Bosnian Muslims, in Bosnian politics.

Implications for U.S. Policy

How should the United States respond to demographic issues affecting its security interests? Nichiporuk writes that a combination of research and analysis, development assistance, and focused military preparedness can help the United States protect its strategic interests in the face of demographic challenges.

First, the U.S. intelligence community could improve its long-run strategic position by paying more attention to demographic indicators and warning measures. It could place more emphasis on understanding how demographic pressures can constrain the actions of allies, increase frictions between regional powers, and spur ethnic conflict.

Second, the United States could target foreign aid more precisely to help achieve foreign policy objectives. Targeting foreign aid can enable the United States to help developing nations better manage the effects of rapid population growth, allowing them to conserve resources and to undertake political reform. In some circumstances, U.S. foreign aid could help developing states reduce fertility rates outright. Recent RAND research, for example, has shown that a number of women in developing countries have an interest in reducing their fertility rates and that American aid to international family planning programs has been a cost-effective way to help them do so. [1]

Finally, the increasing urbanization of the world population calls, as many U.S. military leaders recognize, for new tactics, training, and technologies for urban warfare. In the short term, U.S. forces can gain the greatest improvement here through training. Over the long term, the United States will need new technologies so that its ground troops can operate more effectively in urban areas. These should include more-advanced unmanned aerial surveillance platforms, better personnel protection gear, and improved nonlethal weapons.


  • [1] See Rodolfo A. Bulatao, The Value of Family Planning Programs in Developing Countries (MR-978-WFHF/RF/UNFPA).

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