After graduating from high school in 1986, Timothy McVeigh was restless. He had dropped out of business school and worked at a couple of jobs, including one as an armed security officer. Tired of fielding his neighbors' complaints about shooting weapons on his own property, McVeigh decided in 1988 to join an organization that not only allowed its employees to shoot but also encouraged them to do so—the U.S. Army. McVeigh wanted to become an infantryman and hoped to eventually join either the army's Special Forces unit or the Rangers.

McVeigh went through boot camp at Fort Benning, Georgia, where he met two men who would become integral parts of his future—Terry Nichols and Michael Fortier. Nichols and McVeigh became close friends during boot camp despite the difference in their ages. (Nichols, thirtythree, was the oldest recruit in the company.) Many of the soldiers...