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Two corps of the Army of the Potomac were under General McClellan's control at Alexandria. They were General Sumner's Second Corps and General Franklin's Sixth Corps. This totaled 25,000 troops. McClellan saw General Pope as incompetent and did not want to waste good troops to save Pope's hopeless situation. General in Chief Henry W. Halleck ordered McClellan to send these troops to reinforce Pope. McClellan held back these troops as long as possible. McClellan also urged General Pope to not engage the Rebel troops and to retreat to the north.
On September 16, 1862, one day before the historic Battle of Antietam, Major General George B. McClellan lost his best opportunity to defeat General Lee's army in detail in Maryland. McClellan was slow to assemble his forces in and around the town of Sharpsburg, Maryland. McClellan was unaware that he substantially outnumbers Lee's army and postpones an attack on the Confederates. Instead he waits another day until his reserve forces joins his main army. Theoretically, if McClellan conducted an assault on September 16, the Battle of Antietam would have been a smashing Union victory.
On September 15, 1862, Major General George B. McClellan made a miscalculation that would have made a significant impact on the Battle of Antietam. In fact, that battle would have taken place on that date instead of September 17, 1862. On the 15th McClellan could have attacked General Lee's forces at Sharpsburg but he hesitated. He believed he did not have enough troops, when in fact he had 40,000 troops as compared to Lee's 18,000 troops. Clearly, this would have changed the history of the US Civil War, and may have ended that war in a very short time, as Lee's army would have been devastated.
Union General George B. McClellan had a loyal staff of Union army generals. McClellan's chief of staff was his father in law.
General George B. McClellan's telegraph to Secretary of War Edwin Stanton on June 28, 1862 bordered on treason. When McClellan's telegraph was received by General Dix in Washington DC, Dix omitted McClellan's claim that the Lincoln administration purposely acted to create the Peninsula campaign as a failure.
Two corps of the Army of the Potomac were under General McClellan's control at Alexandria. They were General Sumner's Second Corps and General Franklin's Sixth Corps. This totaled 25,000 troops. McClellan saw General Pope as incompetent and did not want to waste good troops to save Pope's hopeless situation. General in Chief Henry W. Halleck ordered McClellan to send these troops to reinforce Pope. McClellan held back these troops as long as possible. McClellan also urged General Pope to not engage the Rebel troops and to retreat to the north.
On August 25, 1862, General Halleck asked General McClellan to go to Alexandria Virginia and expedite the forward movement of General William Buel Franklin's Vl Corps . Halleck had already communicated to Franklin that he was to head south to reinforce Pope's army. McClellan countermanded those orders explaining to Halleck that Franklin lacked sufficient draft animals and wagons to move his artillery. He added that the absence of cavalry scouting made such a march dangerous. And, McClellan claimed that until the Vl Corps disembarked from their sea transport, sending Franklin would be a serious error.When Stonewall Jackson struck at Manassas, he cut Pope's communications. There is no way to ascertain as to whether Franklin's advance as ordered by General Halleck could have prevented that. With that said, it's clear that if Franklin had been allowed to march south he certainly would have made Jackson's raid on Manassas more complicated and more difficult.
Lincoln's response to General McClellan's command was that Lincoln relieved McClellan of Command.
As Major General George B. McClellan was following the Confederate army in Maryland, he sent to Washington DC on September 10, 1862, that the Rebel forces numbered 120,000 soldiers. This was a gross error as Lee had less than 50,000 troops. McClellan's source of information on this was from a civilian observer.
As the actual Battle of Antietam was soon to take place, General McClellan miscalculated the number of troops that Confederate General Robert E. Lee had on September 15, 1862, just two days from the Battle of Antietam.In actuality, Lee had only one half of the troops that General McClellan believed he had. If McClellan had attacked Lee's forces on the 15th of September, by all counts, the Army of Northern Virginia would have lost an overwhelming amount of its troops. As it happened, Lee had only 18,000 troops ready to fight versus McClellan's 40,000 troops. McClellan failed to attack.
He wasn't. Meade wasn't replaced at all. He was in at the end. McClellan had been replaced by Burnside after the Battle of Antietam in September 1862 for failing to pursue and destroy Lee's army.
General George B. McClellan was not happy with President Lincoln's initial Emancipation Proclamation of September 22, 1862. He learned of it on September 24, 1862. McClellan discussed possible responses to the proclamation with his closest confidants. As this was happening, officers loyal to McClellan, were said to be speaking about a possible military dictatorship. McClellan, however, was never involved in that. What he did do was to speak to his Democratic friends in New York City to determine how New Yorkers would respond if he openly opposed Lincoln's proclamation.
Union General William B. Franklin graduated from West Point in 1843. Among the graduating class of 39 cadets, Franklin ranked first. He saw significant action on the Peninsula Campaign. There, under General George B. McClellan, Franklin led the VI Corps. He also led the same Corps in the Battle of Antietam.
On September 16, 1862, one day before the historic Battle of Antietam, Major General George B. McClellan lost his best opportunity to defeat General Lee's army in detail in Maryland. McClellan was slow to assemble his forces in and around the town of Sharpsburg, Maryland. McClellan was unaware that he substantially outnumbers Lee's army and postpones an attack on the Confederates. Instead he waits another day until his reserve forces joins his main army. Theoretically, if McClellan conducted an assault on September 16, the Battle of Antietam would have been a smashing Union victory.
Union General George B. McClellan received the battle plans for the Confederate invasion of Maryland on September 13, 1862. He recognized the value of knowing Lee's plans and the opportunity he had to catch and defeat Lee. McClellan immediately informed President Lincoln of this opportunity.
On September 30, 1862, General in Chief telegraphed General McClellan that he was very pleased about the battle reports furnished by McClellan on the victory at South Mountain and Antietam. His congratulations were overwhelming and he promised to convey all of this to President Lincoln.
Via telegrams and letters, General George B. McClellan recognized that the carnage on September 17, 1862 was the most horrible battle he had ever witnessed or read about. He said Antietam was the horrible "battle of the age".