This paper highlights the relevance of moral authority, and the role that egoistic ethical claims have in waging war. This is done, in view of the just war tradition, by drawing a parallel between the crusades in the 'kingdom of heaven' proclaimed in 1095, and the present Islamic jihad, as well as the Bush administration's declaration of a war on terror. It maintains that the role of self-legitimized leaders is crucial in shaping the order of the jus ad bellum criteria, in both Christian and Muslim societies, and that the indiscriminate usage of just war rhetoric proves to be a formidable weapon. Moral authority is described as a power resource, capable of capsizing the relevance of ethics, subjecting the interpretation of justice to declar...