Hmm. If we want to preserve our diverse cultures, then we have to do more to defend our own cultures against immigrants imposing their cultures over them.
How you do that without being outright racist is the tough part.
How do immigrants impose their cultures on a host country? Can you give some examples? Historically populations mix by migration, wars, slavery, and trading networks. It is a process that cannot be stopped, maybe slowed down or accelerated. The disappointing aspect of it, is now this process has been hijacked by corporations. How did the West acquire a culture of coffee or coffee-shops? Now is McDonalds and Costa Cafes.