Conflicts and tensions may arise not only because of political and military threats to national sovereignty. They may also result from environmental degradation and the pre-emption of development options which do not lend themselves to conventional military solutions to threats to national sovereignty. Unanticipated and unplanned environmental change may well become the major non-military threat to international security and the future of the global economy.
In addition to the environmental stress caused by warfare, there is now increasing concern that environmental degradation and resource shortages may actually cause armed conflict. Examples of environmental degradation capable of escalating into violence include severe water shortages, widespread desertification, health-threatening toxic contamination, and refugee flight from environmental wastelands. Even within nations, increasing demands for limited natural resources create domestic tensions, as well as intensifying the pressure between private and public interests. National security is now increasingly dependent on environmental security.
The conference statement of the World Conference on the Changing Atmosphere : Implications for Global Security (UNCED/UNEP/WMO, Toronto June 1988) drew attention to the issue that the continuing alternation of the global atmosphere threatens global security, the world economy and the natural environment through: (a) climate warming, rising sea-level, altered precipitation patterns and changed frequencies of climatic extremes induced by the "heat trap" effects of greenhouse gases; (b) depletion of the ozone layer; and (c) long-range transport of toxic chemical and acidifying substances. It added that these changes will: (a) imperil human health and well-being; (b) diminish global good security, through increases in soil erosion and greater shifts and uncertainties in agricultural production, particularly for many vulnerable regions; (c) change the distribution and seasonal availability of freshwater resource; (d) increase political instability and the potential for international conflict; (e) jeopardize prospects for sustainable development and the reduction of poverty; (f) accelerate the extinction of animal and plant species upon which human survival depends; and (g) alter yield, productivity and biological diversity of natural and managed ecosystems, particularly forests.
The problem of water supply provides the most acute examples of current national insecurity due to environmental factors, especially in the case of semi-arid countries. Some Arab countries consider that their access to three of the region's vital rivers (the Euphrates, the Jordan and the Nile) is being threatened by the non-Arab countries upstream. Thus Turkey is now controlling the flow of the Euphrates as part of a major dam project. Israel diverts some of the Jordan river flow for irrigation, leaving little for Jordan itself. Egypt is concerned at the implications of irrigation projects of Ethiopia and Uganda which could affect the flow of the Nile.
Soil erosion in the highlands of Ethiopia during the 1960s, caused primarily by deforestation, resulted in a decline in farmland fertility and a hefty falloff in agriculture, followed by food shortages and spiraling prices. It all culminated in riots in Ethiopia's cities, eventually precipitating the overthrow of Emperor Haile Selassie in 1974. This was the first time a government had been ousted for primarily environmental reasons.
The former Soviet Union is awash with nuclear materials. Radioactive waste litters the landscape, poorly protected stockpiles of highly enriched uranium and plutonium grow, the sarcophagus built to contain 64,000 tons of radioactive materials at Chernobyl is cracking, and a persistent criminal element strives to gain access to weapons grade materials.
In 1998 the USA Secretary of State, stressed the environment as a national security and diplomatic issue, on the theory that environmental degradation leads to political unrest, cross-boarder tensions, economic set-backs and the flight of refugees.