However, one main difference people in this thread seem to forget is that America’s civilian kills were about dealing damage to an enemy country within enemy territory. It’s horrific but the main difference was that Germany mass executed and actively tortured civilians within its own territory. America never did that and as horrific and regrettable Japanese internment camps were, and full of racism and prejudice, and failing to even uphold the Constitution and just being abject failures in treating people humanely, comparing them to Nazi concentration camps indicates a complete and utter failure in understanding how different the situation was; America was not trying to actively exterminate Japanese citizens within its borders as a matter of policy.
The closest American came to Nazi Germany was the persecution of black people within its borders but even while Nazi germany was inspired by Jim Crow in terms of how to treat Jews, it’s a failure to recognize that Nazi Germany ran off with the idea when they started setting up death camps. The closest American came to that was lynchings which never reached the scale or official government sanction that concentration camps did.
The closest American could be said to have done that was the Trail of Tears and their treatment of Native Americans; American has always struggled to contain the racist instincts of a significant part of their population but it is not unique in this challenge.