Portions of this article have been drawn from Thomas Homer-Dixon, Jeffrey Boutwell, and George Rathjens, "Environmental Scarcity and Violent Conflict," Scientific American, February 1993; and from Homer-Dixon, "Environmental Scarcity and Global Security" Headline Series (New York: Foreign Policy Association, 1993). The author thanks the participants in the Project on Environmental Change and Acute Conflict, especially project co-directors Jeffrey Boutwell and George Rathjens. The Donner Canadian Foundation funded the article's preparation.

1. Thomas Homer-Dixon, "On the Threshold: Environmental Changes As Causes of Acute Conflict," International Security, Vol. 16, No. 2 (Fall 1991), pp. 76-116.

2. The three-year Project on Environmental Change and Acute Conflict brought together a team of thirty researchers from ten countries. It was sponsored by the American Academy of Arts and Sciences and the Peace and Conflict Studies Program at the University of Toronto.

3. On simple-scarcity conflicts, we examined water in the Jordan and Nile River basins and the Southern African region; on environmentally induced group-identity conflicts, we focused on Bangladesh-Assam and the Miskito Indians in Nicaragua; and on economic decline and civil strife, we studied the Philippines and China. Researchers in the project also investigated the 1989 conflict in the Senegal River basin, the 1969 Soccer War between El Salvador and Honduras, the rise of the Sendero Luminoso in Peru, migration and civil strife in Haiti, and migration from black homelands in South Africa.

4. For example, see David Wirth, "Climate Chaos," Foreign Policy, No. 74 (Spring 1989), pp. 322; and Neville Brown, "Climate, Ecology and International Security," Survival, Vol. 31, No. 6 (November/December 1989), pp. 519-532.

5. Diana Liverman, "The Impacts of Global Warming in Mexico: Uncertainty, Vulnerability and Response," in Jurgen Schmandt and Judith Clarkson, eds., The Regions and Global Warming: Impacts and Response Strategies (New York: Oxford University Press, 1992), pp. 44-68; and Diana Liverman and Karen O'Brien, "Global Warming and Climate Change in Mexico," Global Environmental Change, Vol. I, No. 4 (December 1991), pp. 351-364.

6. Peter Gleick provides a potent illustration of the effect of population growth on water scarcity in Table 3 of "Water and Conflict: Fresh Water Resources and International Security," International Security, Vol. 18, No. 1 (Summer 1993), p. 101.

7. The second and third types of scarcity arise only with resources that can be physically controlled and possessed, like fish, fertile land, trees, and water, rather than resources like the climate or the ozone layer.

8. Since population growth is often a main cause of a decline in the quality and quantity of renewable resources, it actually has a dual impact on resource scarcity, a fact rarely noted by analysts.

9. James Boyce, "The Bomb Is a Dud," The Progressive, September 1990, pp. 24-25.

10. Bernard Nietschmann, "Environmental Conflicts and Indigenous Nations in Central America," paper prepared for the Project on Environmental Change and Acute Conflict (May 1991); and Sergio Diaz-Briquets, "Comments on Nietschmann's Paper," ibid.

11. Jeffrey Leonard, "Overview," Environment and the Poor: Development Strategies for a Common Agenda (New Brunswick, N.J.: Transaction, 1989), p. 7. For a careful analysis of the interaction of population and land distribution in El Salvador, see chap. 2 in William Durham, Scarcity and Survival in Central America: The Ecological Origins of the Soccer War (Stanford, Calif.: Stanford University Press, 1979), pp. 21-62.

12. Global Assessment of Soil Degradation, World Map on Status of Human-Induced Soil Degradation, Sheet 2, Europe, Africa, and Western Asia (Wageningen, the Netherlands: United Nations Environment Programme [UNEP], International Soil Reference Centre, 1990).

13. Nafis Sadik, The State of the World Population 1991 (New York: United Nations Population Fund, 1991), p. 24; World Resources Institute [WRI], World Resources 1992-93 (New York: Oxford University Press, 1992), pp. 246 and 262.

14. Despite popular perception and the past claims of the United Nations Environment Programme, many experts now believe that the African Sahel (which includes southern Mauritania) is a robust ecosystem that does not exhibit extensive human-induced desertification. There is no clear southward march of the Sahara desert, and ecosystem recovery can be rapid if there is adequate rainfall and a reduction in grazing pressures. See "The Ebb and Flow of the Sahara," New York Times, July 23, 1991, p. B9. Overgrazing across the western Sahel, and the consequent migration of people from the region, appear to arise from the expansion of sedentary farming and population growth that together concentrate pastoralists on smaller areas of land (an example of ecological marginalization). In general, pastoralists are weak in the face of modern African states; state development since decolonization has often changed property rights at their expense. See Olivia Bennett, ed., Greenwar: Environment and Conflict (London: Panos, 1991), chap. 3, pp. 33-53.

15. G.M. Higgins, et al., Potential Population Supporting Capacities of Lands in the Developing World, Technical Report of Project INT/751P13, "Land Resources of the Future," undertaken by the UN Food and Agriculture Organization (FAO) in collaboration with the International Institute for Applied Systems Analysis (IIASA) and the UN Fund for Population Activities (Rome, 1982), Table 3.5, p. 137.

16. Michael Horowitz, "Victims of Development" Development Anthropology Network, Bulletin of the Institute for Development Anthropology, Vol. 7, No. 2 (Fall 1989), pp. 18, and Horowitz "Victims Upstream and Down," Journal of Refugee Studies, Vol. 4, No. 2 (1991), pp. 164-181.

17. Jacques Belotteau, "Senegal-Mauntanie: les graves evenements du printemps 1989," Afrique Contemporaine, No 152 (April 1989), pp. 41-42.

18. Miriam Lowi, "West Bank Water Resources and the Resolution of Conflict in the Middle East," Occasional Paper No. 1, Project on Environmental Change and Acute Conflict (September 1992); see also Lowi, "Bridging the Divide: Transboundary Resource Disputes and the Case of West Bank Water," International Security, Vol. 18, No. 1 (Summer 1993), pp. 113-138; and Natasha Beschorner, "Water and Instability in the Middle East," Adelphi Paper No. 273 (London: International Institute for Strategic Studies [IISS], Winter 1992 93).

19. There appears to be an impending crisis, for example, from salinization of aquifers beneath the Gaza Strip, where the pressure on water resources is "rapidly becoming intolerable"; Beschorner, "Water and Instability," pp. 14-15. The Gaza aquifers are connected to the coastal aquifer that is vital to Israel. Salinization can cause irreversible physical changes in aquifers; even if replenished with fresh water, their capacity is reduced. See Fred Pearce, "Wells of Conflict on the West Bank," New Scientist, June 1, 1991, pp. 3738.

20. Lowi, "West Bank Water Resources," p. 34.

21. Since 1967, the irrigated area on the West Bank has dropped from 27 percent of the total cultivated area to 3.5-6 percent. Beschorner, "Water and Instability," pp. 14 and 78.

22. The best cropland lies, for the most part, in the coastal plains of the archipelago's islands. Landowning and manufacturing elites are closely linked, and their relative economic power has actually grown since independence: the top 10 percent of the country's families controlled 37 percent of the nation's total income in 1985, up from 27 percent in 1956. See Richard Kessler, Rebellion and Repression in the Philippines (New Haven: Yale University Press, 1989), p. 18.

23. Using a standardized figure of 100 for 1972, average real wages dropped from 150 in the early 1950s to about 100 in 1980. Kessler, Rebellion and Repression, p. 26.

24. A full account can be found in Maria Concepcion Cruz, et al., Population Growth, Poverty, and Environmental Stress: Frontier Migration in the Philippines and Costa Rica (Washington, D.C.: WRI, 1992).

25. World Bank, Philippines: Environment and Natural Resource Management Study (Washington, D.C.: World Bank, 1989). Erosion rates can exceed 300 tons per hectare per year, ten to twenty times the sustainable rate.

26. Gareth Porter and Delfin Ganapin, Jr., Resources, Population, and the Philippines' Future: A Case Study, WRI Paper No. 4 (Washington, D.C.: World Resources Institute, 1988).

27. For a full elaboration of the argument in this section, see Homer-Dixon, "The Ingenuity Gap: Can Developing Countries Adapt to Environmental Scarcity?" paper prepared for the Project on Environmental Change and Acute Conflict (March 1994).

28. Arthur Westing, "Appendix 2. Wars and Skirmishes Involving Natural Resources: A Selection from the Twentieth Century," in Arthur Westing, ed., Global Resources and International Conflict: Environmental Factors in Strategic Policy and Action (Oxford: New York, 1986), pp. 204210.

29. See Durham, Scarcity and Survival.

30. Peter Gleick, "Water and Conflict," Occasional Paper No. 1, Project on Environmental Change and Acute Conflict (September 1992); and Gleick, "Water and Conflict: Fresh Water Resources and International Security," International Security, Vol. 18, No. 1 (Summer 1993), pp. 79-112.

31. In 1980, Egyptian President Anwar el-Sadat said, "If Ethiopia takes any action to block our right to the Nile waters, there will be no alternative for us but to use force"; quoted in Norman Myers, "Environment and Security," Foreign Policy, No. 74 (Spring 1989), p. 32. See also chap. 6, "The Nile River," in Thomas Naff and Ruth Matson, eds., Water in the Middle East: Conflict or Cooperation? (Boulder, Colo.: Westview, 1984), pp. 125-155.

32. "Pretoria Has Its Way in Lesotho," Africa Report (March-April, 1986), pp. 50-51; Patrick Laurence, "A 'New Lesotho'?" Africa Report (January-February 1987), pp. 61-64; "Lesotho Water Project Gets Under Way," Africa Report (May-June 1988), p. 10. See also Charles Okidi, "Environmental Stress and Conflicts in Africa: Case Studies of African International Drainage Basins," paper prepared for the Project on Environmental Change and Acute Conflict (May 1992).

33. See Thayer Scudder, "River Basin Projects in Africa," Environment, Vol. 31, No. 2 (March 1989), pp. 4-32; and Scudder, "Victims of Development Revisited: The Political Costs of River Basin Development," Development Anthropology Network, Vol. 8, No. 1 (Spring 1990), pp. 1-5.

34. Astri Suhrke, "Pressure Points: Environmental Degradation, Migration, and Conflict," Occasional Paper No. 3, Project on Environmental Change and Acute Conflict (March 1993).

35. Ibid.

36. The relationship between flooding and soil fertility is ill-understood. See James Boyce, "Birth of a Megaproject: Political Economy of Flood Control in Bangladesh," Environmental Management, Vol. 14, No. 4 (July/August 1990), pp. 419-428, especially p. 424.

37. James Boyce, Agrarian Impasse in Bengal: Institutional Constraints to Technological Change (Oxford: Oxford University Press, 1987), p. 9.

38. Sadik, The State of the World Population 1991, p. 43.

39. Controversy surrounds the question of whether Himalayan deforestation contributes to flooding; see Centre for Science and Environment (CSE), Floods, Flood Plains, and Environmental Myths (New Delhi: CSE, 1991), especially pp. 68-69. On the Farakka Barrage, Ashok Swain writes: "It has disrupted fishing and navigation [in Bangladesh I, brought unwanted salt deposits into rich farming soil, affected agricultural and industrial production, changed the hydraulic character of the rivers and caused changes in the ecology of the Delta." See Swain, "Environmental Destruction and Acute Social Conflict: A Case Study of the Ganges Water Dispute," Department of Peace and Conflict Research, Uppsala University (November 1992), p. 24.

40. Sanjoy Hazarika, "Bangladesh and Assam: Land Pressures, Migration, and Ethnic Conflict," Occasional Paper No. 3, Project on Environmental Change and Acute Conflict (March 1993), p. 52-54.

41. "A State Ravaged," India Today, March 15, 1983, pp. 16-21; "Spillover Tension," India Today, March 15, 1983, pp. 22-23. The 1991 Indian Census showed that Assam's population growth rate has declined; the conflicts in Assam in the early 1980s appear to have encouraged many migrants from Bangladesh to go to West Bengal instead.

42. Hazarika, "Bangladesh and Assam," pp. 60-61.

43. Boyce, Agrarian Impasse.

44. See Shaukat Hassan, "Environmental Issues and Security in South Asia," Adelphi Paper No. 262 (London: IISS, Autumn 1991), pp. 42-43; P.C. Goswami, "Foreign Immigration into Assam," in B.L. Abbi, ed., Northeast Region: Problems and Prospects of Development (Chandigarh, India: Centre for Research in Rural and Industrial Development), pp. 35-59; and Susanta Dass, Spotlight on Assam (Chanderpur, India: Premier Book Service, 1989).

45. Robert Repetto, "Balance-Sheet Erosion -- How to Account for the Loss of Natural Resources," International Environmental Affairs, Vol. 1, No. 2 (Spring 1989), pp. 103-137.

46. This estimate does not include the economic costs of lost rooting depth and increased vulnerability to drought, which may be even larger. See Wilfrido Cruz, Herminia Francisco, and Zenaida Conway, "The On-Site and Downstream Costs of Soil Erosion in the Magat and Pantabangan Watersheds," Journal of Philippine Development, Vol. 15, No. 1 (1988), p. 88.

47. Ed Barbier, "Environmental Degradation in the Third World," in David Pearce, ed., Blueprint 2: Greening the World Economy (London: Earthscan, 1991), Box 6.8, p. 90.

48. Vaclav Smil, "Environmental Change as a Source of Conflict and Economic Losses in China," Occasional Paper No. 2, Project on Environmental Change and Acute Conflict (December 1992).

49. It is hard to judge gross economic activity in China and convert these figures into dollars. Perhaps because of this, the World Bank has not increased its estimates of per capita annual GNP in line with the rapid expansion of the Chinese economy. Smil suggests that the Bank's current annual figure of $370/capita may be too low by a factor of four. This judgment is supported by recent re-evaluations of China's GNP by the International Monetary Fund. See World Bank, World Development Report, 1992 (New York: Oxford University Press, 1992), p. 218; and Steven Greenhouse, "New Tally of World's Economies Catapults China into Third Place," New York Times, May 20, 1993, p. At.

50. Some of the best studies of this question have focused on the relationship between poverty and urban violence in the United States. See William Ford and John Moore, "Additional Evidence on the Social Characteristics of Riot Cities," Social Science Quarterly, Vol. 51, No. 2 (September 1970), pp. 339-348; and Robert Jiobu, "City Characteristics and Racial Violence," Social Science Quarterly, Vol. 55, No. 1 (June 1974), pp. 52-64.

51. People are said to be relatively deprived when they perceive a widening gap between the level of satisfaction they have achieved (usually defined in economic terms) and the level they believe they deserve. Deprivation is said to be relative to some subjective standard of equity or fairness; the size of the perceived gap depends upon the beliefs about economic justice held by the individual. See Ted Gurr, Why Men Rebel (Princeton: Princeton University Press, 1970).

52. Steven Finkel and James Rule, "Relative Deprivation and Related Theories of Civil Violence: A Critical Review," in Kurt and Gladys Lang, eds., Research in Social Movements, Conflicts, and Change (Greenwich, Conn.: JAI, 1986), pp. 47-69.

53. Ibid.

54. These beliefs are grounded in historical and economic experience. See, for example, James Scott, The Moral Economy of the Peasant: Rebellion and Subsistence in Southeast Asia (New Haven: Yale University Press, 1976), pp. 1-11.

55. Homer-Dixon, "On the Threshold," pp. 105-106 and 109-111.

56. See Farrokh Moshiri, "Revolutionary Conflict Theory in an Evolutionary Perspective," in Jack Goldstone, Ted Gurr, and Farrokh Moshiri, eds., Revolutions of the Late Twentieth Century (Boulder, Colo.: Westview, 1991), pp. 4-36; and Goldstone, "An Analytical Framework," ibid., pp. 37-51.

57. For a review of some of these factors, see Jack Goldstone, "Theories of Revolution: The Third Generation," World Politics, Vol. 32, No. 3 (April 1980), pp. 425-453.

58. Wayne Cornelius, Jr., "Urbanization As an Agent in Latin American Political Instability: The Case of Mexico," American Political Science Review, Vol. 63, No. 3 (September 1969), pp. 833-357; and Abdul Lodhi and Charles Tilly, "Urbanization, Crime, and Collective Violence in 19th Century France," American Journal of Sociology, Vol. 79, No. 2 (September 1973), pp. 296-318.

59. Sanjoy Hazarika, "Week of Rioting Leaves Streets of Bombay Empty," New York Times, January 12, 1993, p. A3.

60. The Huk rebellion in the late 1940s and early 1950s provides some of the best evidence for the link between economic conditions (especially unequal land distribution) and civil strife in the Philippines. See Benedict Kerkvliet, The Huk Rebellion: A Study of Peasant Revolt in the Philippines (Quezon City, Philippines: New Day Publishers, 1979); and E.J. Mitchell, "Some Econometrics of the Huk Rebellion," American Political Science Review, Vol. 63, No. 4 (December 1969), pp. 1159-1171.

61. Celso Roque and Maria Garcia, "Economic Inequality, Environmental Degradation and Civil Strife in the Philippines," paper prepared for the Project on Environmental Change and Acute Conflict (1993).

62. Maria Concepcion Cruz and Robert Repetto, The Environmental Effects of Stabilization and Structural Adjustment Programs: The Philippines Case (Washington, D. C.: World Resources Institute, 1992). See also Francisco Lara, Jr., "Structural Adjustments and Trade Liberalization: Eating Away Our Food Security," PPI Research Papers (Quezon City: Philippine Peasant Institute [PPI], 1991); and Robin Broad, Unequal Alliance, 1979-1986: The World Bank, the International Monetary Fund, and the Philippines (Quezon City: Ateneo de Manila University Press, 1988).

63. Kessler, Rebellion and Repression, pp. 24-25.

64. Ibid.

65. Ibid, pp. 16-19. See also Reynaldo Clemena Ileto, Pasyon and Revolution: Popular Movements in the Philippines, 1840-1910 (Manila: Ateneo de Manila University Press, 1979).

66. Cynthia McClintock, "Why Peasants Rebel: The Case of Peru's Sendero Luminoso," World Politics, Vol. 37, No. 1 (October 1984), pp. 48-84; and McClintock, "Peru's Sendero Luminoso Rebellion: Origins and Trajectory," in Susan Eckstein, ed., Power and Popular Protest: Latin American Social Movements (Berkeley: University of California Press, 1989), pp. 61-101.

67. McClintock, "Why Peasants Rebel," pp. 61 and 63.

68. Ibid., p. 63.

69. Ibid., p. 82.

70. Francis Wilson and Mamphela Ramphele, Uprooting Poverty: The South African Challenge (New York: Norton, 1989); George Quail, et al., Report of the Ciskei Commission (Pretoria: Conference Associates, 1980), p. 73.

71. See Mamphela Ramphele and Chris McDowell, eds., Restoring the Land: Environment and Change in Post-Apartheid South Africa (London: Panos, 1991), and Chris Eaton, "Rural Environmental Degradation and Urban Conflict in South Africa," Occasional Paper of the Trudeau Centre for Peace and Conflict Studies, University of Toronto, June 1992.

72. WRI, World Resources, 1992-93, p. 286.

73. Global Assessment of Soil Degradation, World Map on Status of Human-Induced Soil Degradation, Sheet l, North and South America.

74. Thomas Weil, et al., Haiti: A Country Study (Washington, D.C.: Department of the Army, 1982), pp. 28-33.

75. Anthony Catanese, "Haiti's Refugees: Political, Economic, Environmental," Field Staff Reports, No. 17 (Sausalito, Calif.: Universities Field Staff International, Natural Heritage Institute, 1990-91), p. 5.

76. Elizabeth Abbott, "Where Waters Run Brown," Equinox, Vol. 10, No. 59 (September/October 1991), p. 43.

77. Marko Ehrlich, et al., Haiti: Country Environmental Profile, A Field Study (Washington, D.C.: U.S. Agency for International Development, 1986), pp. 89-92.

78. WRI, World Resources, 1992-93, p. 246.

79. Ibid., p. 272.

80. Smil, "Environmental Change as a Source of Conflict and Economic Losses in China", Jack Goldstone, "Imminent Political Conflict Arising from China's Environmental Crises," Occasional Paper No. 2, Project on Environmental Change and Acute Conflict (December 1992).

81. See, for example, Barber Conable and David Lampton, "China: The Coming Power," Foreign Affairs, Vol. 72, No. 5 (Winter 1992/93), pp. 133-149. In their assessment of the pressures on contemporary China, the authors devote only half a sentence to demographic and environmental stresses.

82. Griffith Feeney, et al., "Recent Fertility Dynamics in China: Results from the 1987 One Percent Population Survey," Population and Development Review, Vol. 15, No. 2 (June 1989), pp. 297-321; Shanti Conly and Sharon Camp, "China's Family Planning Program: Challenging the Myths," Country Study Series, No. 1 (Washington, D.C.: Population Crisis Committee, 1992).

83. Nicholas Kristof, "China's Crackdown on Births: A Stunning, and Harsh, Success," New York Times, April 25, 1993, p. A1.

84. For a full analysis, see Jack Goldstone, Revolution and Rebellion in the Early Modern World (Berkeley: University of California Press, 1991).

85. Goldstone, "Imminent Political Conflicts Arising from China's Environmental Crises," p. 52.

86. Ibid., p. 54.

		TOP
	Part 1	Part 2	Part 3
	Environmental Security Database		Publications on the Web