From an article I read earlier today regarding the reaction of the folks in Berlin, THE Nazi capital back in the day, and how America has no clue what 'white supremacy' can do to a nation if done on the scale it was with Hitler and the 'final solution.' The "concrete and barbed wire" walls are referring to the concentration camps. There is a lot of truth in this statement.

"America has yet to deal with the lessons of our own history. We have never been utterly conquered so that we had to. The lessons of slavery and Jim Crow segregation–all predicated on claims of white supremacy–have yet to be fully learned or even fully acknowledged. Our walls are not made of concrete and barbed wire, but they remain walls."

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