Acts of valor. Supernatural faith in the face of death. Five Catholic chaplains have received the nation’s highest military award — the Medal of Honor. Two of them also have their causes for sainthood underway. As Memorial Day is solemnly marked across the United States May 28, the Register remembers these heroic chaplains, recalling their remarkable bravery and their courageous response to the needs of their fellow men in war. Father Joseph O’Callahan was the first Catholic chaplain to receive the Medal of Honor. His friends couldn’t imagine this Jesuit, head of the math department at Holy Cross College in...