 He learned that flanking movements (used by Scott at Cerro Gordo) are often better than frontal assaults, and the value of siege operations (Veracruz).He witnessed Scott's success in balancing political with military affairs and his good relations with the civil population as he invaded, enforcing strict discipline on his soldiers to minimize damage to property.McClellan also developed a disdain for volunteer soldiers and officers, particularly politicians who cared nothing for discipline and training.