The book has been criticized by various academic writers, who have empirically, historically, logically, or ideologically challenged its claims (Fox, 2005; Mungiu Pippidi & Mindruta, 2002; Henderson & Tucker, 2001; Russett, Oneal, & Cox, 2000; Harvey, 2000). Political scientist Paul Musgrave writes that "Clash of Civilization" "enjoys great cachet among the sort of policymaker who enjoys name-dropping Sun Tzu, but few specialists in international relations rely on it or even cite it approvingly. Bluntly, Clash has not proven to be a useful or accurate guide to understanding the world."