It was a name synonymous with failure. More than 80 years ago, an Army base in Blackstone, Virginia, was named for George E. Pickett, the defeated Confederate general who led the disastrous “Pickett’s charge” at the Battle of Gettysburg. Now the base is the first of nine named for a Confederate set to be redesignated by the end of this year. On Friday, Fort Pickett will become Fort Barfoot, in honor of Col. Van Barfoot, a World War II hero and a Medal of Honor recipient.