Pope Benedict XVI has weighed in on the sensitive issue of rapport between Islam and the West: He said that violence, embodied in the Muslim idea of jihad, or holy war, is contrary to reason and God's plan, while the West was so beholden to reason that Islam could not understand it. Nonetheless, in a complex treatise delivered Tuesday at the university here where he once taught, he suggested reason as a common ground for a "genuine dialogue of cultures and religions so urgently needed today." In all, the speech seemed to reflect the Vatican's struggle over how to confront Islam and terrorism, as the 79- year-old pope pursues what is often considered a more provocative, hard- nosed and skeptical approach to Islam than his predecessor, John Paul II. As such, it distilled many of Benedict's longstanding concerns, about the crisis of faith among Christians and about Islam and its relationship to violence. And he used language open to interpretations that could inflame...