The purpose of the crusades was to?

The Turks took over Palestine from the Arabs. It became unsafe for Christian Pilgrims to visit The Holy Sites listed in The Bible. The First Crusade had the purpose of capturing Palestine for Christians so that Christian Pilgrims would be safe. After 100 years, Saladin conquered Palestine. The Second Crusade failed to reconquer Palestine. The leaders of the third and fourth Crusades discovered they did not have the forces to recapture Palestine and turned to piracy. Like so many movements that start for noble purposes, the Crusades ended in corruption.