The reason I like looking at the history of the Third Republic rather than 'Weimar' is that its a country with a much older and ingrained Republican and liberal tradition than Germany had at the time

I also think its closer to the current situation of the United States in terms of the status of minorities: After Reconstruction, there was a clear economic motive to continue the repression black people in the South, the end of chattel slavery had been a shock to that system

Now racism is more a sense of resentment of the increasing integration of blacks and other minorities in the mainstream of American society, in the middle class, in prominent public offices etc. This of course has a deep economic dimension, but it's not quite the same.

The anger at racial minorities occupying more prominent roles in society is something like anti-semitism in the Third Republic, where Jews represented both a permanent "foreigness" and threat to "Frenchness" and the encroachment of modernity on "traditional life

The racial anxieties of the 21st century are still directed at the myth of a criminal underclass that needs to be violently controlled, but increasingly focus on the black professional class efforts to gain recognition, and attempt to paint those as a sinister conspiracy

it's worth pointing out that this huge outburst of racial revanchism did not come during the crime wave of the 80s and 90s, but after the election of President Obama, the biggest sign of minority integration into the ruling elite

In the Third Republic, you had the smallholders and shopkeepers, once the backbone of the Democratic Republic, increasingly feel threatened by encroaching modernity and defect to a reactionary nationalism leavened with anti-semitism, they allied with the old anti-Republican elite