WASHINGTON – The Middle East’s seemingly endless conflicts are diverting attention and resources from a graver long-term threat that looms over the whole region: the growing scarcity of water. And the situation will get worse before it gets better – if it ever does get better.

Years of war, careless water supply management, unchecked population growth, ill-advised agricultural policies, and subsidies that encourage consumption have turned a basically arid part of the world into a voracious consumer of water. The trajectory is not sustainable.

Those were the gloomy if unsurprising conclusions of a three-day conference on the subject in Istanbul last week. From Libya to Iraq to Yemen, too many people and too many animals have stretched water resources beyond their limits. Some countries where the urgency is greatest, including Syria and Yemen, are the least equipped to stave off serious water crises.

Jordan, always short of water, has been overwhelmed by a flood of refugees from Syria. Iraq, which once had ample water, has lost critical supplies to war and to dams built by Turkey upstream on the Tigris and Euphrates.

Egypt has twice as many people as it did 50 years ago, with no additional water resources. The isolated Gaza strip has […]