Upon learning of the raid into Maryland by General Lee and his Army of Northern Virginia, Major General George B. McClellan knew he was facing a challenge from the South's best general and its best army. With that in mind, McClellan began to follow the Confederates slowly, making sure that Washington DC and Baltimore, Maryland were secure. He also needed time to reorganize his Army of the Potomac in order to meet Lee's challenge.
President Lincoln sent his newly appointed General in Chief Henry Wager Halleck to visit General McClellan at his headquarters on the Peninsula in July of 1862. McClellan refused to take the a second offensive against Richmond unless he was reinforced. Halleck immediately saw the Union's disadvantage in this situation. Unless Confederate General Lee perceived McClellan as a threat to Richmond, he would be free to use his interior lines to attack either McClellan or the new army in Virginia under the command of General Pope. Halleck's decision proved to be eventful. He ordered McClellan to leave the Peninsula and reinforce Pope in northern Virginia.
The semi-blockade of the lower Potomac River set by Confederate artillery banks seemed to elude McClellan's attention. This problem was basically solved when Confederate General Longstreet, abandoned the "blockade" as he was sure he would not be able to sustain it.
Based on the problems created by Union General George B. McClellan, Halleck was sent to McClellan's headquarters in Eastern Virginia. At his place of retreat, Halleck and Quartermaster General Meigs needed to determine whether the Army of the Potomac needed the 20,000 extra troops McClellan claimed were required to save the Peninsula Campaign. If not, or due some other problem, McClellan would be ordered to return to Northern Virginia.
It seems that Union General George B. McClellan learned that Confederate General Joseph Johnston was wounded at Fair Oaks and Jefferson Davis replaced him with Robert E. Lee. In McClellan's writings about the war he indicated that General Lee would not be a problem. He believed Lee was timid and lacked experience. This idea may have been the result of the time that McClellan's forces pushed Confederates out of western Virginia early in the war. At the time Lee was in charge of Rebels seeking to retain western Virginia but failed. There is no doubt that McClellan knew of Lee before the war.Lee of course had a stellar career before the war and was once the superintendent of West Point. Nevertheless, in June of 1862, McClellan did not fear Lee as Johnston's replacement.
On July 25, 1862, General in Chief Henry W. Halleck visits the headquarters of General McClellan at his Virginia headquarters in Virginia. He brings General Ambrose Burnside with him. Burnside and McClellan are friends. Halleck gives McClellan a choice, and both of them will be a serious problem for McClellan. McClellan must either restart his Peninsula campaign or make a total withdrawal from Harrison's Landing. These troops will be given to John Pope's new Army of Virginia. McClellan's anger with the Lincoln government intensifies. Reportedly he has been receiving letters from his supporters in the North to march on Washington DC and take control of the government. One thing is certain, Burnside reports that anti-government agitation among McClellan's officers seem treasonous to him. The Army of the Potomac is piece by piece brought back to Washington DC to help form General Pope's new army.
President Lincoln's cabinet was astounded that he reappointed General George B. McClellan once again command the Army of the Potomac. The Northern public, newspapers, the military, and the entire Lincoln administration were shocked. This was perhaps one of the most unthinkable acts that Lincoln would perform in the course of the war. The reasons for not reappointing McClellan are:1. President Lincoln held McClellan responsible for the defeat of Pope and the Army of the Potomac at the Second Battle of Bull Run. And understands that McClellan has a problem with engaging the enemy;2. Lincoln's cabinet also blames McClellan, this includes Secretary of War Stanton and generals Pope and McDowell. Stanton's aids claim McClellan with "treason" on Bull Run and soon this is public knowledge;3. General Pope accused McClellan of "deliberate sabotage";4.. The Northern Republican newspapers also blame McClellan for Pope's defeat. They also charge McClellan with treason;5. The former position of McClellan as general in chief, removed in the Spring of 1862, is given to General W. Halleck, who also finds serious faults with McClellan not only for Bull Run, but McClellan's poor showing in the Peninsula campaign; and6. When on the Peninsula, McClellan blames his failure there on the deliberate actions of Lincoln and Stanton.Lincoln's only response is that only McClellan can reorganize the Army of the Potomac after it's terrible defeat at the Second Bull Run.The reappointment of McClellan at this point of the war seems "unbelievable".
To maintain his army on the peninsula leading to Richmond, McClellan faced a huge logistical problem. His army and artillery batteries required 600 tons of supplies daily. He used the York River Railroad to bring his supplies to the battle fronts.
McClellan was better at building an army(training,drilling etc.) than he was at field command(actually using the army in battle). He was often overestimating the numbers of Confederate troops opposing him and he regularly called for more troops to be sent to him when he already had superior numbers.
During the Mexican War, George B. McClellan contracted malaria. Ever since his time in Mexico, McClellan suffered a recurring series of malarial fevers. This health problem lessened his ability to fully command the Army of the Potomac as it reached the outskirts of Richmond.
It is an approach to find solutions to a felt problem, in which all possible options for solving the problem will be presented. See cafeteria approach..
What is the problem of McCulloch v. Maryland?
One overlooked strength of Union General George B. McClellan that may have helped the South was his determination to wait far too long to organize the Union's Army of the Potomac. The long time this took, the more time it gave the South to add to its armies and prepare for battles with the Union forces. His over cautious tendencies were also a problem. In addition, McClellan believed that the Secretary of War, Edwin Stanton was not qualified to be his direct superior.Whatever his failings, McClellan was not afraid to fight, he was overly cautious and used unreliable sources for gathering military intelligence.