The Danish marine biologist Anton Frederik Bruun (1901–1961) is chiefly remembered as an explorer of the deep‐sea fauna and a key figure in international scientific organizations during the 1950s. As the Cold War increasingly permeated the marine sciences and it became too expensive for small states to operate deep‐sea research vessels, he became an asset to the USA's oceanographic establishment as it sought to first assess Soviet strength (in terms of research, technology and logistical capacity) and then to build up American oceanography in response. Bruun's contacts with the USSR – including a visit in 1957 – strengthened his contacts to the American military as well as American oceanographers. His enthusiasm for raising interest in the marine sciences in developing countries could also be matched to American geopolitical goals. Bruun's participation in the Scripps Institution of Oceanography's Naga expedition to the South China Sea and Gulf of Thailand captured the mutually beneficial nature of his American connections. Bruun was able to use the USA to reach distant oceans, while the USA in turn gained from Bruun's prestige as it forged connections with friendly states through science, an increasingly important arena for Cold War competition.