The contrast in experience between the two men disagreeing over war and theology was striking. On the one side was Pope Leo XIV, the first North American to head the Catholic church and the first cleric from the Augustinian order, who this week visited the modern Algerian city where Saint Augustine once lived. For Leo, who wrote his doctoral thesis on Augustine’s ideas, it was the culmination of a lifelong intellectual interest. On the other, the US vice-president, JD Vance, a very recent adult convert to Catholicism with no academic background in the history of the church’s thinking. At the...