Since the beginning of the Iran war, Pope Leo XIV has frequently called for peace, cautioning that the “delusion of omnipotence” makes military force seem preferable to diplomacy. Although U.S. Vice President JD Vance, a Catholic, criticized some of the pope’s comments, a growing choir of Catholic voices has criticized the conflict by invoking the concept of “just war” – an evolving tradition that has guided Christian thinking about war and peace for 1,500 years.
In March, the archbishop of Washington said the war failed “to meet the just war threshold.” A month later, the prelate leading the U.S. military’s Catholic chaplaincy delivered a stark assessment: The war was not justified. The Vatican’s secretary of state raised similar concerns.
Many faiths have teachings about when war is or is not considered justified, including Judaism, Islam and Hinduism. In the Christian just war tradition, battle is never holy – “God does not bless any conflict,” in Leo’s words – but it is sometimes considered necessary.
