Soon after his return to France, Betances became the first secretary to the Dominican Republic's diplomatic mission to France, but virtually assumed the role of ambassador. He also became the commercial representative of the Dominican government in Paris, Bern and London. At one time Betances attempted to be a venture capital partner on a failed enterprise that attempted to commercialize the use of Samaná Bay to benefit the Dominican Republic, and also to prevent foreign interests (particularly the United States) from taking over the bay, which was considered a primary strategic geographical feature of Hispaniola, in both commercial and military terms.