He sought to exterminate the Slavic "Untermenschen" in order to create his Lebensraum for his Aryans. The Soviet Union lost 20 MILLION people as the Nazi war machine killed everyone in their way - and this doesn't count the non-Soviet Slavs of Poland and other countries.
This campaign of extermination was the central theater of European WWII. I read recently that about 90% of German casualties were on the Eastern Front.
US racial laws inspired the Nuremberg Laws. per wiki:
"... antisemitic and racist laws introduced in Nazi Germany on 15 September 1935 at a special session of the Reichstag during the annual Nuremberg Rally of the Nazi Party. The legislation comprised two measures. The Law for the Protection of German Blood and German Honour prohibited marriages and sexual relations between Jews and Germans..." Professor Whitman goes into this in depth in his book cited in the OP.
The US STILL had such laws until 1967, when the Supreme Court ruled them unconstitutional, 22 years after the defeat of Hitler.
The roots of fascism are deep in this country. Let's consider well which "normal" we hope to return to post-Trump.
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