President Donald Trump speaks during a news conference at the White House on April 6, 2026, in Washington, as Defense Secretary Pete Hegseth and Chairman of the Joint Chiefs of Staff Gen. Dan Caine listen.
              AP Photo/Mark Schiefelbein, File

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.

Originally published on theconversation.com, part of the BLOX Digital Content Exchange.

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