ABSTRACT
The idea of just war has been misunderstood in two fundamental ways in discussion over recent decades. The first, that it is the particular doctrine of Christian religion, or even of Catholic Christianity. The second fundamental misunderstanding is that the just war idea is a relic of the past. This chapter shows the results significantly in Hugo Grotius's use of history and his concept of "charity" to shape a transformed idea of just war based in natural law and thus, in theory, able to be agreed to by all. With Vitoria a transformation began that took just war tradition out of the context of values assumed in medieval Christendom and into the new and more pluralistic value context of the modern period. The subsequent development of the humanitarian law of armed conflicts may thus be traced to this transformation of the just war jus in bello to a wholly natural-law basis, as it appears in the thought of Grotius.
