A historian who fought under McClellan at Antietam later summed it up: “His egotism is simply colossal—there is no other word for it.” We tend to think that ego equals confidence, which is what we need to be in charge. In fact, it can have the opposite effect. In McClellan’s case it deprived him of the ability to lead. It robbed him of the ability to think that he even needed to act.
