If anyone has looked at their history books, which I think for many younger American's (and young people in general) and many ignorant ones may ask "whats a history book?"... we kinda started it.
The crusades during the era's of Papal control, were unrestricted examples of total war on a faith... Christianity vs Islam.
They did not hate us nor discriminate against us.... yet we called them infidels and blasphemous barbarians and invaded their home, proceeding to rape, pillage and murder in the name of "god".
My best explanation that I can give is that they (Extreme Muslim Factions) come from a faith that has not evolved.
Islam is a very conservative archaic faith. Its extremist regulation and condemnation of heresy has prevented it from evolving through the centuries. While Islam preaches much good and in fact is almost no different from the Christian bible (in fact Islam is a variant of Christianity), it has not yet had the evolution stages that Western Christianity has gone through.
Right now Islam is going through its version of the "Inquisitional Era", where extreme fervor is taking root in government legislation. We have evolved into freedom of religion (yet many zealots still exist). We represent the largest example of "heresy" and while the standard day to day Muslim could not give two damns what we call God. The ever growing contingent of Muslim extremist nations will eventually pose a SIGNIFICANT problem. We already have considerable problems with Extremist terror organizations. This has already begun to turn into a religious war.
Religious ideology is something that cannot be proved or disproved. It is the single most evil force on planet earth. It controls the faith of human beings to a point where any differentiation from the ideology is considered incorrect or "wrong" and is destroyed.
Many Americans have the view that evolution is a lie, the human race is the only intelligent species in the universe and that we actually did come from two white human beings that lived in a magical garden. Many Muslims have the view that Allah is the creator of all things, that this "god" person is actually the devil, a false god trying to corrupt, and that infidels must be destroyed. Sharia law, etc.. etc.
^^^ These seem ridiculous to level headed human beings, but it shows the raw power that religious faith holds over people. Utilized by a government which BELIEVES its ideology, and given all the resources that a modern nation can possess, nuclear weapons, armies, political pull.....
And we have a very VERY serious problem.