Even if there were immigrant enclaves caused by the Great Wave in 1925 mass immigration was cutoff. That Act greatly encouraged and speeded up the assimilation process. Today there appears to be no end in sight and illegal immigration isn't helping matters.
In sight of what, human procreation?
JMO, you have unmasked yourself as a Sierra Club member or sympathizer(i.e zero population growth, abortion, etc. etc), hiding behind and flaming the very small xenophobe and racist wing of the right.