America has NEVER had any demonstrated success in assimilating large numbers of people from THIRD-WORLD cultures. These are not the same things.
America is NOT a nation of immigrants, it is a nation of SETTLERS, who historically have from time to time allowed the migration of others from similar FIRST-WORLD cultural backgrounds, and then with great effort–accompanied by decades-long HARD PAUSES on immigration–ASSIMILATED those peoples from similar cultures, such that those peoples ABANDON their original culture and adopt the American heritage culture.
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Who Watches the Watchers? 