De-salination of seawater was an important issue during the Cold War for several reasons:
1) It was a potential source of freshwater in a crisis. As the Cold War intensified, there were concerns about the possibility of nuclear warfare disrupting global freshwater supplies and food production. De-salination could help provide an alternative source of freshwater in the event of such a catastrophe.
As a Soviet scientist noted in 1961, "In the event of radioactive contamination of sources of fresh water, desalinization acquires exceptional importance as amethod of providing countries with fresh water."
2) It demonstrated technological prowess and innovation. Developing large-scale desalinization was a challenging engineering problem, and solving it effectively demonstrated the superiority of a nation's science and engineering capabilities.
Both the US and USSR invested heavily in desalinization research and development to showcase their technological advancement. Some key statistics:
•The US spent over $1 billion (in 1960s dollars) on desalinization research between 1947 to 1969.
•The USSR's Maritime Deserts Experimental Station was established in 1950 specifically to develop desalinization technologies. They claimed to have achieved a capacity of 4,000 cubic meters per day by the late 1960s.
•In the US, Desalinization Act funding in 1961 led to the construction of five large desalinization research plants, with the goal of developing a technology that could produce 1 million gallons of freshwater per day at a cost of $0.05 per 1,000 gallons.
•By 1970, US researchers claimed to have reduced the cost of desalinization to $0.025 per 1,000 gallons, making it more economically viable.
3) It held the promise of restoring freshwater and increasing agricultural output in arid regions. Successful desalinization could help make deserts bloom by providing freshwater for irrigation. This was appealing both for the possibility of expanding territory and proving the superiority of a system/ideology.
In summary, de-salination was an important issue in the Cold War as it represented a potential life-saving technology, a demonstration of scientific-technological achievement, and a solution for increasing resources - all of which were valued by both the US and USSR for ideological, territorial and security reasons. Does this help explain why it was such a big deal? Let me know if you would like me to elaborate on any part of the answer.