Michael Scheuer, former chief of the Counterterrorist Center's Bin Laden unit, resigned from the CIA in November 2004 after 22 years of federal service devoted to national security issues related to South Asia and Islamic extremism. Because of the CIA's pre-publication requirements, he anonymously wrote the bestseller Imperial Hubris as well as Through Our Enemies' Eyes: Osama bin Laden, Radical Islam, and the Future of America. Scheuer contends that Arab antagonism to the West (and even non-fundamentalist Arab regimes' winking at terrorism) has its root in real grievances that have gone unaddressed by U.S. measures.