(with the unstated assumption that the US was just in its choice to fight the Axis)
I actually don't think Smedley would have changed his message at all; I think he started from a false premise that he was 100% convinced of, and would have pointed at the enormous profits made by war industrialists in the US during WWII. He might not also notice that post-war US was the most economically productive country of all time, that it opened up huge options of African Americans, or even really recognize quite what motivated Hitler and the Nazis.