When cultures collide, sometimes they borrow good ideas from each other, and sometimes bad ideas.
The encounter of Islam and the Christian West has given us algebra, but we have also taken over some of the unlovelier products of Islam.
Islam spread the idea of jihad as meaning not only an interior struggle against evil but physical, military operation against the enemies of true religion, against the infidel. The West thought this was a good idea and developed the idea of a crusade, a war that was not simply just but holy, to counter the jihad that had conquered large sections of the Christian world. Christians killed in the name of God.
Islam, submission, developed the idea that God was absolutely unknowable, that our only response to him was to submit to his will, that is will was arbitrary, that all occurred because of his will, and that he could change his will as he pleased because it did not express his nature, which is absolutely unknowable. Hydrogen and oxygen combine to produce water because God wills it; the independence of secondary causes was neglected. God could change the moral law, and command what he had forbidden, and forbid what he had commanded. Our only duty is to submit to his inscrutable will.
The lines of influence are not clear, but I suspect that nominalism and voluntarism in the West are the result of an encounter with this Islamic idea. It sounds so pious.
Slavery had died out in the West, but then Islamic slavers – the Barbary pirates – enslaved perhaps a million Europeans, a process that continued until the nineteenth century. In desperation the papacy allowed slavery to revive in Catholic lands.
And now the Norwegian terrorist Anders Behring Breivik has, as the newspapers point out, issued a manifesto that is the mirror image of Al-Queda. Islamic terrorism has created Christian terrorism.
A recent survey of the values of European youth confirmed that young men are less religious than young women – no surprise there. The report is in somewhat opaque sociological language, but it also indicates that young men are more hostile than women to other religions, even if the men do not believe in the traditional religion of their country. That is, the young men may be indifferent or hostile to Christianity, but they are even more hostile to intruding foreign religions, such as (the report did NOT go on to say) Islam.
In fact, historically European men have been hostile to the clerical-feminine manifestations of their religion. Instead men feel an identification with the religious community, whose identity they have celebrated and defended in their own way. Mussolini was asked to allow the construction of a mosque in Rome; he said certainly, as soon as a Catholic church was built in Mecca.
And so we have a Norwegian, who seems to have shown little interest in prayer, liturgy, or other clerical-feminine manifestations of Christianity, observes Al-Queda and decides he is going to defend the Christian identity of Europe by provoking a civil war between Christianity and Islam.