Some have said that the events of September 11 took every American by surprise. That's not true. There were Cassandras among us warning about the dangers of Islamic terrorism--and one of their leaders was Steven Emerson, who must be ranked among the most fearless reporters in the world. As a self-made expert on Islamic terrorism, he has invited the hatred of violent murderers. (At least one group has marked him for assassination; he was offered enrollment in the federal witness protection program, but refused). For more than 10 years, Emerson has soldiered on, studying groups that operate in the United States for the express purpose of funding and managing deadly organizations. American Jihad summarizes what he has learned, and it isn't comforting. Emerson shows how the Palestinian terrorist group Hamas has grown an extensive network in the United States, how the group Islamic Jihad set up shop at the University of South Florida, and how an Islamic center in Tucson helped recruit two of Osama bin Laden's top deputies. He also provides circumstantial evidence that bin Laden himself once applied for an American visa--"even the possibility is tantalizing, and chilling," he concludes. He urges Americans to fight back, but worries that time is short: "We are still vulnerable." This is an important book, and a sobering one. --John Miller