Not just water, but also resources: electricity, RAM and Flash memory, other things being over-consumed by the AI development explosion. This war doesn't have geographic or national boundaries, its the (heavily funded) AI companies vs everyone else.
Paolo Bacigalupi is to the climate crisis what William Gibson is to cyberpunk. Stories like The Water Knife and The Tamarisk Hunter feeling a lot closer to reality everyday. But then again, fighting over access to water is a tale as old as time.