I was watching an interview a year or so ago of a Muslim who had converted to Christianity, or he may have been a Jew who converted (I apologize I can't remember for sure), anyway, this man had gotten into a tense conversation with a Imam somewhere in Seattle at a local festival, and the Imam informed him that nothing the U.S. did mattered, because they had calculated that when the Muslim population reached 10% in the U.S., that they would be able to take over the economy; and when the number reached 20%, that they would take over the government, AND all the stuff going on in European countries where the Muslims have immigrated in high numbers.
All one need do to realize that is not an unlikely scenario is to look at all the concessions local govt. and businesses are already making to accommodate Muslims.