One of the two cultures will win. The other will be wiped out. "Multiculturalism" tries to sell the fantasy that people from wildly different cultures can co-exist as neighbors. While this IS possible when small numbers of people are brought into another culture, and they assimilate to the new culture, it will not work on a grand scale. The people flooding into Europe are not there to become European, or to even respect European culture. They are NOT assimilating into European cultures. They have their own ideas on how the country should be, and they will implement those things if their culture wins that struggle.