Heroes. Every nation, in every time, seems to need them. Some heroes who often were regarded harshly in their lifetime – e.g., George Washington – gained luster in later years. Others, hailed in their day, have fared less well with the passage of time. Cases in point: William F. "Buffalo Bill" Cody, whom history reviles for his part in stripping our western plains of bison. U.S. Grant betrayed a weakness for whiskey, Charles A. Lindbergh for the appeal of Naziism. One hero whose halo remained fairly fixed has been Davy Crockett, the 19th century frontiersman who's revered among 189 brave...