Violence in the Qu'ran is cited as proof of their violent nature. You could find violence in Jewish, Christian and Islamic holy literature. Doug studied the issue, not from a scriptural base, but from a social assimilation basis. He took a number of myths and researched to see if there was any truth. The myths were false.
One myth was that these newcomers would out breed the natives. It has been found that the birth rate of Muslims in European and English speaking North America gradually converge with the locals. Overlooked is the fact that many immigrants come from rural areas where birth rates are higher, but when people move to urban areas birth rates decline. He uncovered studies in France and Germany that demonstrated lowering fertility rates over time.
Muslims supposedly are not willing to integrate. An American study revealed that 49% of Muslims claimed to be Muslim first and American second, but that evangelicals claimed to be Christians first at a 70% clip. American Muslims tended towards the American view that negotiations were possible between Israeli and Palestinians although in the Middle East this view was not as common. One of the strongest indicators of integration is inter-marriage and he found evidence in many countries involving Muslims.
We have a history with "outsiders" that is playing out with Muslims. Roman Catholics from southern Europe and Jews have gone through a similar route. They were not accepted and viewed suspiciously for decades. Jews fled eastern Europe in the 1880's. In 1909 26% of Jews in United States were illiterate. There was a lot of fear of radical Jews, but gradually they integrated. At about the same time a lot of southern European Catholics emigrated to America and were mightily resented.
Are there dangerous people amongst the immigrants and should we be wary? You can find dangerous people amongst all groups of people. You have to realize that abuse and isolation sometimes bring out the worst of people. Terrorists tend to have political motives, not driven by religion.
All immigrants will adjust more easily with more educational support. And I might add enlightened neighbours.
All immigrants share some of their culture. Jews fried fish and French Huguenot settlers fried potatoes to make the British staple of Fish and Chips. Italians have spread pizza around the globe. Middle Eastern Muslims have brought fallafels and hummus.
"The Myth of the Muslim Tide" is not a long or difficult to read book. It has enough hard data and clear thinking to make all but the hard bigots pause. Examine your own life and history and you will find that the "outsiders" always seem strange and threatening. Given enough time any group of people will tend to interact with other groups and have positive effects on one another.