At first glance, the Catholic faith today in Portugal seems as central a part of everyday life as when the conservative dictator António de Oliveira Salazar’s autocratic regime ruled the country with the tacit approval of the hierarchy in the mid-20th century. 

Adults and young children alike still attend traditional festas and participate in religious processions, often carrying aloft life-size flower-adorned statues of Jesus, Mary and Sao Antonio de Lisboa, the 13th-century Portuguese Franciscan friar who is known to most Catholics the world over as St. Anthony of Padua. Priests and bishops are still called upon to bless fishing fleets or new bridges, and the roads into Fatima are often jammed with religious pilgrims. 

Even so, when Pope Francis arrives in Lisbon on Aug. 2 for the 42nd international trip of his papacy and his fourth World Youth Day — a major gathering of Catholic youth that takes…