James Ford Rhodes (18481927). History of the Civil War, 18611865 1917.
their object. Lee awaited them with his small force. His Maryland campaign so far was a failure. Circumstances had beaten him and only a decisive victory could bring back that prestige which was his when he marched out of Frederick. Philadelphia and Harrisburg were no longer in danger, but his own army stood in jeopardy.
The general opinion is that McClellan should have fought Lee before the Harpers Ferry detachments rejoined him, instead of waiting until September 17 when he had to contend with the whole army. On this day was fought the battle of Antietam, a day of isolated attacks and wasted efforts. Seventy-five thousand Union soldiers endeavored to overcome fifty-one thousand Confederates, Lee handling the inferior force in a manner absolutely above criticism. The Union loss in killed and wounded was 11,600, the Confederate about the same.1
The Victory was McClellans as, on September 19, Lee withdrew from the field and re-crossed the Potomac into Virginia. At the time it was exasperating to think how much more McClellan might have accomplished but, as we see it now, no other result was probable as long as McClellan was McClellan was McClellan and Lee and Lee; still, to overcome Lee in any way and on any terms was matter for congratulation. His army had marched through the streets of Frederick full of pride and hope, singing The Girl I Left Behind Me; now it was a horde of disordered fugitives. And the state of feeling at the North had changed from despondency before South Mountain to positive buoyancy after Antietam.2