Islamic cultural invasion
The Islamic cultural invasion is a phenomenon wherein the liberal embrace of cultural diversity, and fear of racism and intolerance, is exploited by powermongers either within the Islamic community or within the government of the invaded country or both.
This primarily seems to be happening in Europe, though there have been repeated warnings of it happening in the United States as well. So far, the US warnings have not panned out and appear largely to be the result of fearmongering in the other direction (i.e. against Muslims), typically by Christian fundamentalists.