This same question might be rephrased as follows:
"How was it possible for Communist dictator Joseph Stalin to arrest the Jews of Moscow, and publicly charge them with the "Crime of being 'cosmopolites'"?
It is my belief that the Jews, being a homeless, stateless people for two thousand years unable to live as a normal "rooted" people developing their own unique arts and cultures, learned to gravitate to the largest modern cities, which were the areas of progress and interaction with other nations and cultures.
It was the "cosmopolitan" centers where "the wandering Jew in Exile" could immerse himself in the best cultural contributions of "others".
The Jews, being an industrious people who valued education, were always "haunted" by the inner knowledge that they could never find full acceptance by the majority culture around them.
Because the Jews prospered in metropolitan areas, those with wealth soon substituted "philanthropy" and "social activism" in futile endeavors of finding acceptance among the nations.
Centuries of this peculiar lifestyle became an ingrained "habit" of Jewish life in the Exile, so much so that we still see Jews congregating in the major metropolitan cities.
Even in America today, Jews generally seek out professions as attorneys, doctors, financiers, accountants, management, and other professions which enable their status of wealth to substitute for the true security of a people deeply rooted in the land of their ancestors.
As the old adage goes, "It's hard to teach an old dog new tricks!"