MANSFIELD TOWNSHIP, N.J. -- Roy Decker can look at the photos and letters now, more than 16 years later, and spot the clues with ease. Right there, in sweeping cursive, the writings of his former Army roommate and future FBI's Most Wanted fugitive are eerie now. Right there is the Hitler reference, with future serial bomber and alleged Nazi sympathizer Eric Robert Rudolph referring to himself in a 1989 letter to Decker as "Der Furher (sic), Adolf Rudolph." Right there, on the snapshot taken by Decker at their Army camp in Kentucky in 1988, is the portrait of future survivalist...