Final answer:
General George B. McClellan drilled his troops extensively due to his cautious approach and his incorrect belief in the overwhelming strength of the Confederates. President Lincoln, along with Secretary of War Edwin Stanton, ordered McClellan to invade the Confederacy and capture Richmond, growing increasingly frustrated with his reluctance to engage. McClellan's failure to act decisively led to his dismissal.
Step-by-step explanation:
Why General McClellan Drilled His Troops Excessively
General George B. McClellan was known for his extensive drilling of his troops due to his cautious nature in engaging the enemy. McClellan underestimated his own strengths and overestimated the Confederates', which led him to believe that the Confederate forces were too powerful to defeat.
Consequently, his training routines aimed to prepare his troops meticulously for combat, believing this precision would compensate for what he perceived as the enemy's superior numbers.
President Lincoln's Directive
Frustrated with McClellan's hesitancy and lack of aggressive action, President Lincoln and Secretary of War Edwin Stanton ordered McClellan to invade the Confederacy, targeting the capture of Richmond.
Despite McClellan's advantageous position and superior numbers, his cautious strategy at crucial moments, such as during the Seven Days Battles and the battle of Antietam, ultimately prevented a decisive victory.
This string of missed opportunities and his failure to press the advantage led to his eventual dismissal by President Lincoln, who sought a more aggressive commander to lead the Union forces to victory.