This article explores biopolitical practices that extend beyond national borders and take the whole of humanity as their province. It looks at how attempts to secure and optimize conditions of living in Africa are not merely governmental in scope but also diplomatic in their conceptualization and conduct. It specifically examines the merging of diplomacy, defence and development (or the 3Ds), which purports to optimize life and shape ways of being in areas that cannot be ‘fully governed’ or resist domestication. It assesses the impact of diplomatic pluralization, characterized by the militarization of diplomacy and development, the diplomatization of the military, and new forms of diplomatic outreach, as practised by agencies such as AFRICOM. At stake in this exploration is an ethico-political critique of 3D engagement through which lives, conducts and relationships are negotiated in the postcolony.