As a military leader, George McClellan was known for

George McClellan was a major general during the American Civil War. Nicknamed “Young Napoleon” and “Little Mac,” he twice was commander of Army of the Potomac, the Union's largest army, and fought as general-in-chief of the Union army until being removed by Abraham Lincoln in 1862.

Explanation:

b) the confederacy had to pay all union war expenses.

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