SoCal,

I get your point about how Duke was used to paint Trump.
Duke made the public endorsement for a reason though. I don't know enough about him to quite compare Duke to Hitler, BUT...Hitler's message wasn't accepted by the German people at first.....years later when the political and social climate was different, people were more receptive to what he was saying. Duke might see Trump's ascension as a sign that people are more willing to accept what he (Duke) is saying.