It wasn't the US that death camp inmates feared
The fact that the US stayed out of the World War II until they were attacked proves their belligerence was not, in fact, rampant.
I'm sure that, by the time the US entered the war, Czechoslovakia, Poland, Denmark, Norway, Belgium, Luxembourg, Holland, France, Yugoslavia, Greece and the people of Russia would have been more concerned about the belligerence of Nazi Germany.