Weaponised Citizenship: Should international law restrict oppressive nationality attribution? effects mostly ‘within the legal system of the State conferring it’ but can also have serious consequences for other states and for the stability of the international legal order. International law norms must not only be able to retrospectively evaluate whether the state engaged in the act of nationality attribution has committed an abuse of rights in this process, but rather pro-actively guide and constrain nationality ascription. International law could, for example, develop default rules proscribing mass naturalisations outside the state’s territory barring exceptional situations such as statelessness. It could also establish principles for evaluating what types of conduct would constitute valid individual consent for the purposes of extraterritorial nationality attribution and the circumstances and fora in which host countries could challenge this attribution. These would just be the first steps towards recalibrating an international filing system for nationality that seems to be seriously compromised. Rather than trying to tinker at the margins with a system that was designed for a different era, a serious overhaul would be in order. European University Institute 6