This article analyses political questions pertaining to the Chagos Archipelago (British Indian Ocean Territory). In particular, it highlights the interrelatedness of various public policy issues that the extant academic literature has treated as distinct: (i) the US military presence on Diego Garcia; (ii) UK efforts to protect the natural environment of the Chagos Islands; and (iii) the human rights of the exiled Chagossians, the indigenous people of the Chagos Archipelago. The concept of a trilemma is used to illustrate the unhelpful way in which the interrelatedness of these issues currently is portrayed by the relevant political actors. The article concludes with recommendations for how the trade-offs between military security, environmental and human rights objectives could be made less stark in the interests of all concerned.