Atlantropa
en.wikipedia.org
en.wikipedia.org
The utopian goal was to solve all the major problems of European civilisation by the creation of a new continent, "Atlantropa", consisting of Europe and Africa, to be inhabited by Europeans. Sörgel was convinced that to remain competitive with the Americas and an emerging Oriental "Pan-Asia", Europe must become self-sufficient, which meant possessing territories in all climate zones. Asia would forever remain a mystery to Europeans, and the British would not be able to maintain their global empire in the long run and so a common European effort to colonise Africa was necessary.
It is like the British “pacifist” Prime Minister David Lloyd George who was for European disarmament except for blacks:
“We insisted on reserving the right to bomb niggers." So David Lloyd George explained the British government's demand at the 1932 World Disarmament Conference to keep the right to bomb for "police purposes in outlying places". Airpower had shown its value in spreading what Winston Churchill, when defending in 1919 the use of poison gas against "uncivilised tribes", had called "a lively terror".
https://www.theguardian.com/books/2011/dec/07/britains-empir...
Meanwhile, I find this more interesting: https://en.wikipedia.org/wiki/U.S._Army_Corps_of_Engineers_B...
The Army Corps of Engineers literally built a scale model of the San Francisco Bay Area, and they used it to figure out that damming the SF Bay was a very, very bad idea: https://www.youtube.com/watch?v=i70wkxmumAw
In the absence of accurate computation modeling (either hardware or physics models) in the 1940s-70s, it's a pretty ingenious way to simulate complex hydraulic systems.
And as for Atlantropa, think about it in these terms: (a) a large, funded public-works program in Europe, just as the Nazi Party was gaining support and before the Spanish Civil War, (b) substantial amount of cheap, carbon-free energy for Europe and North Africa by now, & (c) a pan-European effort ~50 years before most EU structures.
You'd have a hard time convincing me that would have been doomed to turn out worse than actual history.
[0] https://en.m.wikipedia.org/wiki/Mississippi_River_Basin_Mode...
It's interesting that the Mississippi model's scale was specifically chosen to minimize unrealistic effects of surface tension, that might have dominated at a smaller scale. (But it was the 1940s, and I'm sure we know more about surface tension and hydrodynamics now)
Off topic, is there a reason why comments do not support HTML anchor elements?
[1] https://www.vegvesen.no/en/roads/Roads+and+bridges/Road+proj...