Because he said one thing in public and another in private. Several independent sources attest to the peculiarity of his beliefs and his private disdain for traditional Christianity.
Every time a Creationist tries to attach Nazi to Darwin they are going to get this and it is appropriate.
No it isn't, because you're distorting the truth, and that's never appropriate. You don't win an argument against a troll by descending to his level.
No one wins, but sometimes you have to illustrate an absurdity with another absurdity.
I only know of two people who have changed their minds on evolution. One of them is Michael Denton.
It is always appropriate to fight fire with fire.
Earlier on this thread we got the usual crap that Communists came from Evolution. I posted threads to show, conclusively, that that is crap. But it will appear again, probably from the same sources. Did (do) these facts win an argument? No.
So saying that Darwin spawned Nazism is rationally idiotic, but the only way to get through the crap is to show that Hitler was a professed Christian, by his own words, and therefore just as easily attached to Creationists as to Darwin, and that is true. The argument is not sound either way, but perhaps it will penetrate the fog and make them think that by smearing Charles Darwin with either Communism or Nazism, they can be just as easily smeared with the same.
Until they see that guilt by, in many cases just "supposed" association, is a false argument, they need to be reminded that smearing cuts both ways. Thus we see the references to fundamentalist Islam and other crackpot anti-evo groups like the Hare Krishna.
Smearing is a tactic of the Left. Sometimes it works, but it is usually phony.
We see petitions saying "scientists" disagree with Evolution. We see Project Steve in favor of Evolution. Both are phony arguments. The only real true arguments concern the mountains of evidence for evolution. In all my hours here in Crevoland, I have never seen a Creationist attempt to undermine this evidence. They can't, so they resort to smearing.
Should we react with just a yawn?