It seems the Arab Spring, which toppled long-ruling autocrats only to expose simmering religious and sectarian conflicts in the region, did succeed in bringing renewal to one of the countries it swept through three years ago. Tunisia, where the uprising began with the self-immolation of a desperate young street vendor, marked the three-year anniversary this week of the overthrow of President Zine el Abidine ben Ali, the first of the region's decades-long leaders to be ousted in the heady atmosphere of revolution in 2011. Marches through Tunis, the capital, evoked both the gains and setbacks of the post-Ali era, with Tunisians celebrating their evolution from repression to...