I love a Crusades debate!
Then they later get distorted and all but fogetten. The Initial reasons for going into the crusades were that Islam threatened to invade and engulf Catholic europe. At one stage they had invaded 70% percent of europe and some of these countries remain islamic to this day. The holy Roman empire was partially invaded and the west several centuries later when the effects became clear and anti-christianity/anti-west ideals set in, decided to do something about it. Christians on pilgramage were being beheaded and terrorised(their heads were being piked and put outside the pilgrimage sites so other fellow pilgrims would see). Some Islamic leaders threatened to destory Holy christian sites, such as Golgotha.
I don’t know about this. The high tide of Islamic expansion had come and gone by 1100. It was already rolling back in Spain, and the Byzantines were beginning to recover from the disaster at Manzikert. The emperor Alexius had no need for whole crusading armies. He just wanted a few mercenaries, and was caught badly offguard when the Crusaders showed up.
Pilgrimage to Jerusalem was actually getting safer from its low point when the Crusades began. Generally, pilgrimage was safer when a lone Islamic power controlled the Levant. When the caliphate was weak and fractured, bandits tended to be a problem. A second problem was petty emirates collecting high taxes. Regardless, the caliphate tended to be reasonably tolerant (the Turks were less so, but the Arabs and Palestinians were preferred to the Byzantines by Christian sects like the Copts, or even the Jews, who were no longer ruthlessly opressed).
The caliph you are referring to is al-Hakim the Mad, who was a lunatic in general. He did destroy the Church of the Holy Sepulcher, which played a large role in galvanizing the Crusades. Two things about him, though: he was a long time before the crusades, and he was generally regarded by Muslims as the devil incarnate. He was known for wandering the streets and ordering random persecutions. al-Hakim was the exception, not the rule.
Oddly enough, though, the Crusaders themselves receive equal misrepresentation as uniformly bad people, when this is not the case either. The Sack of Jerusalem was disgraceful, and the 4th Crusade was a disaster (if this had never happened, there would not have been an invasion fo the HRE, for Byzantium would have held firm against the Turks). However, once the Franks established themselves in Outremer, they tended to be good kings (with the exception of Reynald de Chatillon and King Guy, who lost Jerusalem).
People like to portray the crusades as one of two things
Evil Europeans invade peaceful Middle East, pillaging, killing and raping.
Noble Christians save good pilgrims from violent, evil Turks, and liberate Jerusalem.
Its much more complex than that.