Over the past decade, experts have discussed the offshore technologies so closely associated with accelerating climate change—namely, offshore oil and gas drilling—as tools for climate action, as was the case at a United Nations roundtable in April 2019. Such experts have frequently used offshore technologies for the construction of flood-resilient floating structures and for zero-carbon energy generation, such as in the case of offshore wind parks, simultaneously tackling the problem of carbon fuel-related air pollution. Such developments draw attention to the intellectual history of ocean industrialization, its driving forces, and related environmental thought. This article examines the intellectual origins of ecomodernism and similar green growth strategies. Using an oceanic perspective and placing the ideas of Japanese star architect and Metabolist movement member Kiyonori Kikutake and US ocean expert John P. Craven at its center, this article argues that their two prototypes of floating industrial combines tested in Hawaii and Okinawa during the early 1970s applied the Japanese Metabolist movement’s design principles of mobility, modularity, and plug-in structures to Pacific waters in an effort to decouple ocean industrialization from the destruction of ecosystems. Several of their proto-ecomodernist ideas, born as techno-optimist reactions to neo-Malthusian fears of resource depletion and overpopulation, have become central pillars of ecomodernist thought. As such, their projects turned into the immediate forerunner of current development strategies whose intellectual aim is to continue growth during (or despite) environmental challenges up to the planetary scale.