The rise of new powers and attendant shifts in the global balance of power have led to calls for UN Security Council reform. Established powers have often responded by linking increased influence in the international system with the assumption of more international responsibility by aspirant powers. Based on ethical and philosophical approaches from the individual and state levels, and a case study of Brazil, this article analyses the way in which the notion of responsibility is discursively constructed, demonstrating the manner in which it has been used as an ever-shifting goalpost to deny emerging powers participation at the highest levels of global strategic decision-making. Most often, this is done by equating “responsibility” with the ability and willingness to use robust military force.