At the same time, some incredibly dangerous wackos failed to assmilite here, such as ...
... the Frankfurt School
... Emma Goldman [who triggered the McKinley assassination]
... Berkman [who tried to kill Carnegie’s business partner].
[Also note the actual battle Goldman and Berkman were involved in between a union and a steel company.]
That's a different problem. That's about whom we allow to immigrate into the country. You will recall that when the Frankfurt School arrived, it was to the open arms of the communists in the Roosevelt Administration.
American communism had a long legacy prior to that. It was the 19th Century practice of the American elite to send their children to Europe for university study that created Roosevelt's red diaper babies.