That is the same excuse people have used to excuse regarding slavery, racism, sexism, antisemitism, homophobia, etc. Documents from the time (i.e. 1850s US) makes it clear that people knew that slavery was horrible.

Your point about Austria is what? My point was that by 1939 Germany had already annexed the Sudetenland and Austria. Jews and other "undesirables" were arrested and sent to camps. Jews had their property stolen or were forced to sell at ridiculously low prices (e.g. The Bristol Hotel in downtown Vienna). This was known to the leaders in the west.

I disagree with your conclusion at the end. The US (see operation Paperclip), had no real problem with the Nazis. GM and Ford had business with the Nazis throughout WWII. If Germany had not declared war on the US, it is debatable if and when we would have gone to war in Europe.

The Soviet Union was another matter. The US invaded Russia in 1917 to try to reinstall the Tsar. We have been in cold and/or proxy wars with the USSR and Russia ever since then, with 1941-45 being the only years we got along.

At the end of WWII, we went immediately back to hating the USSR. I think that our hatred of the USSR was the reason Finland paid no price for working with the Nazis.