The growing importance of non-state actors challenges the traditional inter-state order of public international law. In many respects, the reciprocal logic undergirding state responsibility is difficult to apply and high thresholds for attributing non-state conduct complicate matters even further, which stands in stark contrast to the increase in power on behalf of non-state actors, in particular where they operate in countries that lack the capacities to effectively regulate and control private actions. International law’s traditional way to fill these accountability lacunae has been the recognition of due diligence obligations that require states to diligently prevent and sanction harmful private conduct.