 The most likely source of conflict in the Middle East over the next 20 years is not war or terrorism or revolution, according to a new report by CSIS, it's water. Earlier I spoke with John Alterman, director of the Middle East program here at CSIS and author of a new report, Clear Gold, Water as a Strategic Resource in the Middle East. Agriculture has been a key source of income and subsistence in the Middle East for thousands of years, but with the push by Middle Eastern governments to grow higher quantities of crops that are more water-intensive, the strain on groundwater resources has become unsustainable. Saudi Arabia is an exporter of dairy products, but to make a gallon of milk in Saudi Arabia because of the heat and growing the crops and everything else takes 2300 gallons of water, much of which can never be replaced. Rather than adopting policies that remedy the problem, Middle Eastern governments are often dispensing subsidies that exacerbate wasteful behavior by the public. Subsidizing wealthy farmers to use lots and lots of water makes no sense. To not measure wealthy farmers depleting aquifers as they grow wheat and fruits and other water-intensive crops makes no sense. The reasons for the lack of government action often stem from preoccupation with problems they see as more pressing. Yemen, whose government is currently wrestling with three insurgent movements, provides an excellent example of this phenomenon. They are so preoccupied that they see water and other resources as tools to stay in power rather than things that might threaten their power in 10 years time because if they can't deal with the short-term, the long-term for these leaders is irrelevant. If these governments continue on the same path, the consequences for both internal and regional stability could be severe. Though leaders are treating this issue as a far-off concern, for some countries serious water shortfalls may be right around the corner. The capital of Yemen may go dry as early as 2017, some people say even earlier. How does all this play out within Yemen with a huge migration flow inside the country? Beyond Yemen? We don't know, but you have a young population not highly skilled, dislocated, and angry. I don't know a single country in the world that's looking for a population like that to come across their borders. In their new report, Clear Gold, John Alterman and Michael Jubin of the CSIS Middle East program suggests that there is still hope to avert such crises if governments begin taking proactive measures now. Changing expectations is the first part. If people expect water to be free, people use it as if it's free. You have to monitor water use, you have to measure it, you have to charge people for it. Though these reforms are necessary to ensure a sustainable water supply, governments may find it difficult to change the status quo in societies where water is a key source of political capital. A lot of it has to do with thinking through agriculture and how agricultural strength relates to national strength. And if governments can turn the corner on those issues, I think they could have a profound impact on their water use in a relatively short period of time. To read the full report, visit CSIS.org.