The reason for the dysfunctional behavior of Third World immigrants and their descendants has nothing to do with "prejudice" and everything to do with their own natures and low intelligence.
Somalis, no matter their many, many faults did not "live in caves a few generations back
You’re attributing complex civilizational outcomes—like economic output or social cohesion—entirely to a 'nature' you’ve decided is fixed, while completely dismissing the transformative power of culture, education, and institutional environment.
Benjamin Franklin famously referred to German immigrants in Pennsylvania as "Palatine Boors" who were "swarthy" and would never adopt English customs, fearing they would eventually turn America into a "German colony." Later, during the 19th century, they were suspected of radicalism and refusal to integrate because many held onto their language and social clubs (Vereine).
Then later the 1924 immigration act was specifically passed to limit Italians and Slavs, as they were widely believed to have lower IQs and a higher propensity for crime compared to Northern and Western Europeans.
I would like to offer a third possible explanation for the current dysfunctional behavior of Third-World immigrants in the U.S., and the fact that they are not assimilating - one that makes abs. no reference to I.Q. or the possible genetic component or hereditability thereof:
Cronos is, in part, correct: If the U.S. govt. undertook herculean, expensive efforts to force-assimilate them, they might indeed integrate after a few generations! But -
1. They don't want / see no need to assimilate, and
2. They are actively being instructed by leftists that they shouldn't have to assimilate (because European culture and Western civ are "bad," "ray-cist," etc.). Those represent insurmountable barriers!
These immigrants are being actively taught that we native Americans are "evil" and "guilty." And also that we are simultaneously obliged to coddle them (with welfare programs, preferential hiring practices, etc.).
Cronos is, perhaps, correct that these Third-World immigrants could eventually be integrated, at tremendous cost - but he is blind to the "elephant in the living room": In the current moral and political climate, and with the record-breaking inflow of unassimilated masses, it would be impossible to institute the necessary measures to accomplish that goal - and even if they were imposed, they would be actively resisted every step of the way.
Regards,