In an increasingly polarised global context dominated by identity politics and the resurgence of force as a structuring principle of political order, the normative foundations of peace based on rights and the rule of law appear to be eroding. This paper examines whether the "forgotten principle" of fraternity, which has long been overshadowed by liberty and equality in modern constitutionalism, could provide an alternative legal framework capable of countering the contemporary logic of conflict. Drawing on pivotal 2018 French decisions by the Conseil constitutionnel, which, for the first time, recognised fraternity as a constitutional principle underpinning the humanitarian freedom to assist others, regardless of their legal status, and on parallel Italian case law that indirectly operationalises fraternity through solidarity and the protection of vulnerable persons, the paper argues that these judicial developments point towards an embryonic yet significant relational normativity. However, current jurisprudence only partially captures fraternity's deeper anthropological potential. In an era where religious identities can fuel both conflict and peacebuilding, fraternity, understood not as a communitarian ideal, but as emerging from the universal human experience of vulnerability and suffering, may provide a legal and interreligious framework capable of broadening the scope of the juridical we. In this light, the paper reimagines fraternity as a normative resource for resisting the primacy of force, reshaping debates at the intersection of law and religion, and establishing new peace frameworks that transcend identity-based antagonisms.