The reasons people emigrate to someplace else are often economic – they see little hope for a prosperous life for themselves and their children in their native culture, so the move is to give them the chance for a better life. Perhaps the people are being persecuted within their own nation for their ethnicity, their politics, or their religion, so they seek the freedom to pursue their lives as they choose without persecution or discrimination. No matter what the reason, there presumably must be something pretty bad about someone’s native land and the situation in their destination country must be perceived to be better in that regard. Otherwise, it seems difficult to understand why someone would uproot themselves to go somewhere else. Why leave and go there if there was little prospect to a big improvement?
It seems clear to me that when an immigrant arrives in their new land, they should be willing to live by the laws of their new nation, and to adopt their new culture as soon as possible – that is, to become assimilated into their adoptive nation as soon as possible. This doesn’t mean they have to wipe away any traces of their native culture – but how much pride can you have for the culture and traditions of a nation that you chose to leave?
It’s often the case that immigrants gather together in enclaves of fellow immigrants from the same nation/etnicity, rather than simply dispersing throughout their new land. This way, their neighbors speak their native language, celebrate the same holidays, follow the traditional customs, and so forth. It’s quite natural to seek the company of others of your own kind – tribalism is built into our genes. The problem with this clustering is that it inhibits assimilation. The immigrants seek to retain everything familiar to them, with the exception of whatever negative situation caused them to leave their home land.
If immigrants live by a different set of rules in their enclave from those of their new country, this is permitting at least some (and perhaps most) of what they wanted to leave behind when they left their birthplace. Immigrants have a responsibility to assimilate, to learn the language of their new country, to follow the laws and customs of their new home even as they honor whatever good things they retain about their original culture. Seeking to have some sort of cultural autonomy is to sanction disregard for the laws and customs of their new nation. If they have no respect for those laws and customs, it's illogical to move from your original home to that new country? Go back home and return to the situation you left!
Your huddled masses yearning to breathe free,
The wretched refuse of your teeming shore.
Send these, the homeless, tempest-tost to me,
I lift my lamp beside the golden door!