New York City Mayor Michael Bloomberg, a staunch supporter of the proposed Islamic cultural center and mosque near Ground Zero, recently has been expanding his business dealings in the Arab and Muslim world, including opening a new "Islamic finance portal." Some critics are questioning whether Bloomberg's unpopular decision to back the controversial mosque project may be colored by his billion-dollar financial software, news and data company's decision to build a hub in the United Arab Emirates and North Africa. The mayor's privately held company, Bloomberg L.P., has been increasing its revenue in the Middle East while its U.S.-based division has...