What IS the point of leaving 'there' to come 'here', then wanting to make 'here' 'there'??
Ever been to a German beer garden in Texas or a Czech bakery in Nebraska?
The problem here is of course the unwillingness to integrate, not the desire to keep something of the "old country". Earlier generations of immigrants were more than anxious for their children to become Americans, albeit without completely losing their connection to the old country. For the most part they succeeded in the former, but had less success in the latter.
German immigrants kept their Lutheran, Catholic, or Mennonite religion, in the latter case they remain in fairly isolated communities to this day. However they were not actively hostile to the rest of us, even when the "rest of us" were hostile to them. You still see people in the Amish communities of Pennsylvania and Iowa who cling to the "old ways", and in the Mennonite communities of the great plains who only accept modern practices in their work (generally farming) life, not in their personal or religious life.
Conversion of all the infidels through terroristic means!!!