Despite economic debacles, recurring ​“accidents”, reactor core meltdowns in Chernobyl and Fukushima and the cautious academic reflection it has engendered, civilian nuclear power continues to enjoy legitimacy in energy policy discourse. This may not be the case in all countries. But it is so in a number of influential states, such as, prominently, all the permanent members of the UN Security Council. Why does nuclear power persist in these and other key countries, such as India or Iran and Japan? How is it that economic costs, technology risks and weapons proliferation concerns point in one direction while energy policy and technology choice moves in the other? We suggest that for an important set of select countries this divergence can be ascribed to a ​“discourse of power” that is pegged to domestic concerns and, more importantly, to international relations. This discursive process constructs energy and material abundance as the cornerstone of social stability, political power and ultimately national sovereignty and geopolitical influence. The atom’s energy remains prominent in such imaginaries of abundance, more so in contexts of fossil energy insecurity and climate change. The questioning then of nuclear power by environmental and social concerns has to also question this discourse of power. The latter’s sanguinity vis-a-vis abundant energy needs to be problematised. This is not the case today in international relations. Practitioners focus on the consequences of environmental deterioration. The problem of climate refugees, for example. This paper argues that realist frames of power and self-interest in international relations be acknowledged explicitly as drivers of the discourse of power and in turn the socio-ecological consequences that ensue from this pursuit of cheap and abundant energy. To challenge nuclear power ultimately is to also challenge this medieval yet dominant norm of power play that pervades large swathes of international relations.