In this article, we depart from the emerging norm of responsibility to protect (R2P) and the ideal of coherence. We argue that coherence as an ideal is supported by philosophical as well as psychological arguments as a necessary universal condition for the rational credibility of a belief or a claim. The prominence of coherence as a criterion of rationality makes incoherence problematic – normatively, as well as pragmatically, especially regarding norms with great values at risk. It is argued in the article that the R2P represents such a norm as it aims to prevent grave violations of human rights. In this article, we therefore address troubling incoherence in the conceiving of this norm. To do so, we test the coherence of the International Commission on Intervention and State Sovereignty (ICISS) report, the content of which can be seen as a probable source of a future institutionalization of R2P. The result reveals a fundamental conflict in the report between the implications of R2P and the use in the report of the criteria guided approach often associated with Just War Theory, a conflict that undermines the legitimacy of the norm of R2P.