Trump is taking aim at water supplies for an endangered fish, but scientists say he’s missing the point. It’s one of California’s thorniest problems. The nation’s most populous state is full of sprawling cities, vast farmland, rich ecosystems — and it must decide how to divide scarce water resources among them.

President Donald Trump on Wednesday threatened to withhold federal disaster aid for wildfire-ravaged Los Angeles unless California leaders change the state's approach on its management of water. In a Fox News interview,