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.