They're marrying people of other races. pewsocialtrends.org/2017/05/18/int…
Compared to recent immigrant groups in the past, that's very very high.
Nope. Interracial marriage is HIGHER for the college-educated. pewsocialtrends.org/2017/05/18/1-t…
Were past immigrants to America expected to give up their cultures and customs?
No.
Catholic, Jewish, and Orthodox immigrants were NOT forced to convert to Protestant denominations.
But it didn't work.

But the present era is no different. Hispanics, for example, are adopting English just as fast as previous immigrant groups. washingtonpost.com/news/wonk/wp/2…
Today's immigrants are intermarrying heavily and adopting English. And past immigrants kept their ancestral religions.
So nothing substantive has changed.
My hypothesis: It's liberals' way of welcoming new ethnic groups into the mix.
(That's a fantasy. That's never what assimilation has been like. But we'll come back to that.)
They're scared they'll be forced not just to give up their traditions and identity, but to try in vain to conform to an impossible standard.
They intermarry, form interracial friendships, etc.
But for this reason, over time their culture blends with that of the liberal natives who welcome them into the fold.
Not the nativists' fantasy of submissive conformity.
Rather, a process of INTEGRATION. Of cultural (and eventually, physical) blending into a new and unified whole.
It happens naturally. Without barriers to actively keep them apart, neighbors tend to become one people.
They want a fantasy version (or, better yet, to simply kick newcomers out).
But what WILL really happen is that for better or worse, native culture will change as it blends with that of the newcomers.
This is the future. It's happening very rapidly.
(end)