Word spread quickly through the Charleston Naval Station last June: a big-time terrorist was headed for the brig. An entire wing of the base’s military lockup was emptied out.AND WHEN THE PRISONER arrived—31-year-old Jose Padilla—he was placed in an isolation cell with a lamp burning 24 hours a day and a phalanx of guards around the clock. One inmate asked a guard what exactly Padilla had been charged with. “He’s not charged with anything,” the guard shot back. “We’re just holding him.” The prisoner was baffled. “How the hell can you do that?” he asked.Quite easily, it turns out. Attorney...