The history of Islam is as shady and ambiguous as the history of those cultures from which it borrowed. In addition to this, the Islamic faith makes enormous claims for itself, threatens its adherents with submission or "surrender," and demands of nonbelievers deference and respect in return. There is nothing in its teachings that can even begin to justify such arrogance and presumption. You notice how liberals always say, "If only Islam had a Reformation", but it cannot. Islam claims it cannot. In this respect, it is exceedingly dangerous.
Islam is the most toxic form of religion. To advocate the establishment of a religion-governed state, with the best means of getting there Jihad, holy war, and the idea that Muslims have a special right to feel aggrieved enough to demand such a thing, is an utter nonsense and I think the entire religion of Islam is a total mockery. Rather dangerously, Islam teaches, "Ours is the last and final." There is no possibility of another. This is the final word from God. If you take note, that is a direct invitation to violence and intolerance, one to which they seem quite willing to succumb.
Islam itself is not comparable to Western cultures because the laws of Sharia and ways of living prohibit much of what western cultures practice. The sooner more people question and mock it for how absurd it is, the better.