Final answer:
In historical context, Lee's 'crusade' refers to a religiously motivated military expedition during the Middle Ages, distinct from a pilgrimage or a leisure trip.
Step-by-step explanation:
Lee went on a crusade, which should not be confused with a mere trip or vacation. During the Middle Ages, a crusade was a military expedition initiated by the Christian powers to reclaim holy lands from Muslim control. In contrast, people also went on pilgrimages, which were religious journeys to sacred places for personal devotion, sometimes to seek miracles or forgiveness. While the word 'crusade' has sometimes broadened in modern language to describe any vigorous campaign in the name of a cause, in the historical context, it refers explicitly to these religiously motivated wars, particularly those targeting the Holy Land.