I believe the problem lies in clustering and assimilation. In some areas of the USA, the immigrant population exceeds 30-40%, and these tend to be the loudest v

I believe the problem lies in clustering and assimilation. In some areas of the USA, the immigrant population exceeds 30-40%, and these tend to be the loudest voices. Small towns are hit the hardest, but even large cities are not immune to sudden, rapid population fluctuations and the strain this puts on local resources (just look at New York). The history of the Irish in the United States serves as an excellent example. Driven by the Potato Famine, they poured into the US in massive numbers. When too many people from unrelated cultures arrive too quickly, conflict becomes inevitable. Add 10 to 20 million people over a four-year period, and you have a perfect storm for conflict.