"Full coverage," not your typical fashion show prerequisite, was the theme at a "fashion seminar" recently hosted by Nordstrom at the tony Tysons Corner Center mall in McLean, Va. The show, called "Interpreting Hot Trends for Veiled and Conservative Women," was perhaps the first high-fashion hijab event sponsored by corporate America. The target: well-heeled Muslim women living in the suburbs of Northern Virginia, where mansions and mosques are filled with rich Muslim immigrants, an increasing number of whom shop at Tysons Corner. The Nordstrom show is part of a growing trend: Western retailers and designers are beginning to market directly...