INVISIBLE NATION How the Kurds' Quest for Statehood Is Shaping Iraq and the Middle East By Quil Lawrence Walker. 366 pp. $25.95 In journalistic accounts of the Iraq war, the Kurds, if they are mentioned at all, tend to be used as a counterexample. Kurdistan is a place of relative calm amid chaotic violence. Its construction boom highlights the economic wasteland elsewhere. Its politicians are stalwart partners of the United States in a country bristling under U.S. occupation. A Kurdish public relations campaign describes the region simply as "the other ... (more)