I know a lot of the nationalistic ideals of the Holocaust were pretty heavily grounded in eugenics. My question is more specifically about what was borrowed from the U.S. in terms of things originally being done in the U.S. before being adopted by Nazi Germany.

Where there cases of Hitler saying, “hey, this is what the Americans are doing and it’s a great idea”?

I know some specific practices were borrowed, such as gases used at the Mexico/U.S. border later being used (albeit in much higher concentrations) at Nazi death camps.