There are often wars in places where resources like food and water are scarce. People fight over what little there is, or they see the weakened country as a target for an invasion. Somalia for example, has been in the grip of war for years but also has had significant droughts over the past few years. The two problems are related. http://en.wikipedia.org/wiki/2011_East_Africa_drought
And a lot of people, including me, would love to go there and work on cheap desalinization if we didn't have the certainty that our lives would be at risk, and our work would stand a very high chance of being expropriated by a number of predatory competing quasi-governments in case it does work.
Look at Zimbabwe's food output on a chart and you'll see what I mean.
