It doesn’t need to be “deadly” to represent a declining standard of living and political pressure towards socialism. Parts of Georgia and California have serious water shortages. The whole country has already been subjected to laws requiring toilets that use very little water and as a result don’t flush very well. Obviously this will be a bigger problem as population increases.
The chronic food shortages in some third world countries certainly are deadly, and pose a huge obstacle to political change. People who are starving and whose children are starving don’t have the energy to fight oppressive political regimes and are easily convinced to back new and more oppressive regimes on the promise that the new regime will “give you land” so you’ll be able to grow plenty of food. Check Zimbabwe for a recent example of this scheme — ever wonder why such a huge portion of the Zimbabwean population was eager to put this guy in power? They were having trouble feeding their ever-increasing numbers of children, and desperately wanted to believe his crazy promises.
We have the fresh water in the US to support a lot more (and I mean at full levels, not subsistence), but we don't have the population distribution to take advantage of that.
They have proposed piping water from half a continent away to California for goodness sake!
If I am not mistaken Mugabe came to power in a coup, and runs the government as a military dictatorship. Food production only dropped off as he strangled the country with his policies based on a mixture of racism and socialism.
In the past 20 years or so starvation is almost always caused by corrupt governments not lack of food.