"The importance of Robert E. Lee's first movement north of the Potomac River in September 1862 is difficult to overstate. After his string of successes in Virginia, a decisive Confederate victory in Maryland or Pennsylvania may well have spun the war in an entirely different direction. Why he and his Virginia army did not find success across the Potomac was due in large measure to the generalship of George B. McClellan, as Steven Stotelmyer ably demonstrates in Too Useful to Sacrifice: Reconsidering George B. McClellan's Generalship in the Maryland Campaign from South Mountain to Antietam."--Provided by publisher.