Ten years ago this week, with the horrors of the terrorist attacks of 9/11 still fresh, a mysterious white powder started showing up in the mail. These anthrax attacks killed five and infected 17 people. The FBI spent years and millions of dollars to find the suspect. Bruce E. Ivins became their man in 2008 after he committed suicide. However, a review of the evidence by ProPublica and PBS Frontline shows many questions remain.