This essay aims to be a contribution to the contemporary debate on the “Just War Theory” in a way that challenges traditional concepts of the theory, especially the idea that only sovereign states constitutes legitimate authorities. Using Hezbollah as a case study, the author argues that the organization’s enormous popularity and de facto control over considerable parts of Lebanon makes Hezbollah a legitimate ruler of its territory. Consequently Hezbollah, despite being a non-state actor, should be regarded as a legitimate authority and thus capable of fighting just wars.