McClellan at Antietam

Standing in stark contrast, Stonewall Jackson s classmate at West Point General George Brinton McClellan failed to seize two key opportunities at the Battle of Antietam in September 1862 and a third in the months that followed. His hesitation serves as an excellent example of how the human decision-making process can limit tempo.

McClellan s first failure to seize the initiative occurred four days prior to the battle, when Union soldiers found Lee s battle plans. By midday September 15, McClellan had already amassed seventy-five thousand of his ninety thousand troops at the town of Sharpsburg, directly in front of Lee, whose army included only eighteen thousand troops at the time. ^[9] Lee s forces were split and vulnerable: he lacked a readily available reserve, and he had minimal supporting artillery or cavalry. Despite knowing Lee s precarious disposition, McClellan, making the excuse at approximately 2:00 p.m. on the 15th that it was too late to move, opted to wait before striking. Then stalling again on the 16th, McClellan blamed his delay on obtaining more information, rectifying the position of troops, and perfecting the arrangement for attacks. ^[10] These two delays resulted directly in the standoff that followed at Sharpsburg; Lee used the lapse in time to bring twenty-two thousand additional troops from the South. What ensued was the bloodiest single day of fighting on American soil ”Lee lost nearly eleven thousand of his men, while McClellan lost more than twelve thousand ”without a decisive victory for either side.

McClellan s second failure to seize the initiative occurred after the battle. Although still outnumbering Lee by nearly fifty thousand men, he refused to press the attack on the beleaguered southerners. This time he cited a lack of complete information and inadequate strategic reserves for his inaction. Through the 18th, the Confederate forces were backed against the Potomac River . After realizing that McClellan was not in pursuit, Lee understood that the difficult strategic withdrawal across the river could be accomplished safely without drawing enemy fire, and he was able to slink slowly across the single river crossing back into West Virginia.

For nearly two months following the battle, McClellan declined to give chase and remained rooted at Sharpsburg, even as President Abraham Lincoln pleaded that he renew the attack. For this third and final reluctance to act, which gave Lee valuable time over the fall and winter, to regroup, reconstitute his army, and avoid further contact until he had assembled a more formidable force, Lincoln officially relieved McClellan of his command.

Leadership Lessons

McClellan failed to make decisions and act until he possessed perfect information or until he outnumbered his opponent by a wide margin. Accordingly, he ceded the ability to seize the initiative and dictate the course of events in the encounter. Had he attacked earlier on the 15th, on the 16th, or in the months following the battle, he would have done so from a position of relative strength, and he would have been much more likely to overwhelm the reeling Confederates. Counter to the maneuver philosophy of pressing the attack to accelerate tempo, McClellan favored taking a strategic pause to regroup, think, and await near-perfect information that, given the fog of war and independence of human will, never came.

^[9] Johnson, Curt, and McLaughlin, Mark. Battles of the Civil War: From Bull Run to Petersburg: Four Hard Years of Strategy and Bloodshed , 65.

^[10] McClellan, George B. Report of Major General George B. McClellan, U.S. Army, Commanding the Army of the Potomac, of operations August 14 “November 9, 1862.