It has been called Robert E. Lee's supreme moment: riding into the Chancellorsville clearing...the mansion itself aflame in the background...his gunpowder-smeared soldiers crowding around him, hats off, cheering wildly.After one of the most audacious gambits of the war, Lee and his men had defeated a foe more than two and half times their size. The Federal commander, "Fighting Joe" Hooker, had boasted days earlier that his plans were perfect -- yet his army had crumbled, and Hooker himself had literally been knocked senseless.History would remember the battle of Chancellorsville as "Lee's...