In the 1930s, a German engineer named Herman Sörgel drew up blueprints to dam the Strait of Gibraltar, drain the Mediterranean by two hundred metres, and create a continent-scale agricultural zone to be worked by African labourers. The plan, which he called Atlantropa, attracted serious attention from leading engineers and survived, remarkably, into the 1960s — outlasting the very world war that had made its colonial logic grotesque. It is a useful place to begin any honest accounting of geoengineering, because it shows that the impulse to remake the planet is not a product of the climate crisis. It is something older and stranger in the human character.

That impulse also flourished in the Soviet Union. The engineer P.M. Borisov proposed building a dam across the Bering Strait to melt the Arctic ice cap and warm a country that, as the American climatologist P.

E. Lydolph once observed, simply "lacks heat." Rival Soviet scientists argued the same warming could be achieved more efficiently by excavating roughly 3,000 square kilometres of sea floor along the Wyville-Thomson Ridge — an intervention they apparently considered modest. Both proposals reflected a post-war ideology that treated nature as an engineering problem waiting for a sufficiently bold solution.