They sparked an interest in new ideas. When the men left their hometown to go fight they learned many new cultures and even brought some traditions home. Therefore that also brought new ideas about how things work.
This was the main way in which the Crusades brought about industrial change. Before the Crusades, the contact between different groups of people across several continents was very restricted. Because of this, cultural exchange, although present, was very limited. However, during the Crusades, many people travelled to faraway lands, which led to the exchange of new ideas and ways of living. This sparked an interest that led to industrial change.
The Patriot Act caused a mixed reaction among Americans who believed the measures necessary, but also believed that they could be used for malicious purposes.
