While Gen. George McClellan brooded over Gen. Charles Stone's arrest and continued to rehearse his impending assault upon Richmond, heavy fighting and a new Union war hero emerged in the west. Ohioan Ulysses S. Grant led a combined force of infantrymen and ironclad gunboats in February 1862 to victory at Fort Henry and Fort Donelson, Confederate strongholds on the Tennessee and Cumberland Rivers just below the Kentucky-Tennessee border. An unlikely hero, Grant had left the army eight years earlier after a discouraging post on the Pacific coast. Following a succession of civilian occupations, Grant returned to the army in 1861 and quickly rose in rank and fame. During the battle of Fort Donelson, Grant refused to negotiate terms with the Confederate commander and sent a formal reply: "No terms except an immediate and unconditional surrender can be accepted." The Northern...