FDR, the President referred to the camps where we kept the Japanese Americans in the USA as "concentration camps." I would not presume to argue with the President of the USA.
However the general public tends to call the German camps, "Concentration camps" and so that they do not have to deal with the fact the USA did the same to the J.A.s excluding the killing part, the public wants to call the American camps, "internment camps" or even "relocation camps."
It is like comparing "six" with "half a dozen." Sounds different but basically the same.