In other words, the religion of peace was acting as it always does, but at the time of the Crusades, for various internal political reasons, it had become even more extreme and Christians were motivated to fight back. Here's a little from the Catholic Encyclopedia on hostage ransom, btw:
The redemption of captives has always been regarded in the Church as a work of mercy, as is abundantly testified by many lives of saints who devoted themselves to this task. The period of the Crusades, when so many Christians were in danger of falling into the hands of infidels, witnessed the rise of religious orders vowed exclusively to this pious work. In the thirteenth century there is mention of an order of Montjoie, founded for this purpose in Spain, but its existence was brief, as it was established in 1180 and united in 1221 with the Order of Calatrava. Another Spanish order prospered better; this was founded in the thirteenth century by St Peter Nolasco under the title of Our Lady of Mercy (de la Merced), whence the name Mercedarians. It soon spread widely from Aragon, and has still several houses at Rome, in Italy, Spain, and the old Spanish colonies. Finally, the Order of Trinitarians, which exists to the present day, had at first no other object, as is recalled by the primitive title: "Ordo S. Trinitatis et de redemptione captivorum".
Right, you are. The 10,000 churches that I referred to relates to Caliph al-Hakim, who had them destroyed throughout his domain, including the Holy Sepulchre.
Hearing about how the Crusades were purely an act of Christian aggression really annoys me because it shows 1) a complete willingness to comment on the history of something one knows nothing about and 2) the political motivations for making such a statement in ignorance.