If you're a Christian, the Crusades were hardly anything to be proud of. Church corruption was at the heart of it more so than any thought of liberating occupied lands.
You missed the point. The crusades were less about liberating, than about counter attacks to prevent Europe from falling. In my mind, the crusaders were heroes and should be honoured.
The Crusades were a result of a number of factors. The Muslims had already conquered Spain and Sicily prior to the First Crusade. I believe primogeniture played a larger role than corruption. Primogeniture left a number of knights with no land and plenty of time on their hands.