We Have Argued Over Water Before, and Forgotten the Lesson

There is a temptation, watching Geneva this week, to believe the argument over water is new. It is not. Historian's habit is to reach for the record, and the record is unkind to our sense of novelty: the irrigation empires of the ancient river valleys, the water courts of medieval Valencia that still convene, the aqueduct politics of dry republics — each learned that whoever writes the rules of the flow writes the map of who thrives and who leaves. What is new in 2124 is only the scale. With the global mean anomaly settled at +2.8°C for a fifth straight month and the displaced now past 108 million, the "who leaves" has grown to the size of nations. The Concordat's delegates are not the first to meter a scarce river; they are merely the first to do it for twelve billion people at once. The old water courts survived because they placed the guaranteed share above the tradable one, and never let anyone forget which came first. That is the whole inheritance. Geneva would do well to remember it before Friday, and better still to remember it after.