> Plenty of countries completely rely on desalination already

Let's take Kansas... the largest producer of wheat in the US. https://www.statista.com/statistics/190376/top-us-states-in-...

Kansas wheat crop down 38% from last year https://youtu.be/QjrhAXzEGDc

Kansas cannot run on desalination plants ... there's no salt water. The gulf coast of Texas is 1000 miles away.

While aquifers do regenerate (Groundwater levels in the Kansas High Plains aquifer see first overall increase since 2019 https://kgs.ku.edu/news/article/groundwater-levels-in-the-ka... ) I'm going to point out that news article has seven years of declines previously.

The aquifer that Kansas draws upon is the Ogallala Aquifer ( https://en.wikipedia.org/wiki/Ogallala_Aquifer ) and you can see the rate of depletion at https://www.climate.gov/news-features/featured-images/nation... - there are spots in Kansas where the groundwater dropped by 150 feet from before it was tapped with deep wells to 2015.

Yes, most of the earth is covered by water. Getting that water to Kansas and Nebraska and North Dakota, however, is a problem.