> AND YET! Mysteriously! Japanese were specifically targeted for the harshest treatment, Italians the second most, and the fewest German Americans ended up in concentration camps.
Practically speaking, it would be difficult to round up all German-Americans and put them into concentration camps in WW2. They had basically interbred with other people with dissimilar European ancestry, did not retain any unique accent, or group themselves into ethnic communes.
Additionally, many believed that by fighting against Germany in World War 1, all German-American's had proved their loyalty beyond any more doubt.
Lastly, Germany had its greatest waves of immigration to the America's either before the US was even a nation, or during its infancy.
Italians were a 'new' wave of immigration, pushed into ghettos due to existing social bigotry, and easily differentiated from the normal phenotypic blend of older immigrant populations that became the white American norm.
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Personally, I believe that this is better stated as ethnic discrimination. In Europe, Africa, and Asia---all 'old world' continents---there is less of a tendency to trumpet ones own race. Rather people have the view that their ethnicity is the best, their bloodline lineage is the best, their family heritage is the best. Discrimination there takes the form of Germany believing that anyone who isn't german is low-class---which includes Spaniards, Italians, British, Russians, Poles, Finns, etc.
In the US today, ethnicity has been de-emphasized with a greater focus being put on race and religion, which is to our detriment in understanding both historical treatment of immigrants, and also current day treatment of immigrants.
For example: why are so many people against Syrians, but view Saudi's as tolerable? Why is Yemen seen less favourable than Oman?