A few thoughts on the roots of the Jewish holocaust.
[And thoughts on Stalin's Purges]
[This was in response to a post that I don't think said anything very interesting.]
I'd say Anti-semitism in Europe was mostly upheld by the church until the 20th century. it was a dogma in many sects that the jews as a collective group, a people, betrayed God. And that for God's work to be done the jews will either be converted or destroyed. interpretations of ancient thinkers in a modern context mutated this into a genocidal ideology aspect in various political organisations.
Stalin feared jews too, what with him rounding up the Jewish doctors in the USSR because he feared they'd poison him. And he killed many when the tried the balance out the communist party in his purges, he was suspicious of jews, a prejudice from his youth and from his rivals in communism, such as Trotsky.
The roots of much of the antisemitism with Hitler and Stalin was cultural, based in the church, in the Russia Empire, it was a vast problem, and that didn't fully melt away in the USSR. Stalin's killing of Jews was quite extensive as well, ranging from the 30s to the early 50s when he rounded up doctors. Stalin seems to have prefered to starve his rivals, if he had been more creative then the death camp might have become associated with him more than Hitler.
German national socialist did buy into Tsarist propaganda, The Protocols of the Elders of Zion, and this fuelled antisemitism to a great degree than it otherwise might have done. Scapegoating the jews was an old practice by then, but new fuel for that fire was found from such fabrications. The hatred and scapegoating of Jews in Russia forced many into the communist party, millions suffered.
The main drive for race conflict was the nationalist propaganda, which pitted people who looked the same against each other in strict loyalty to their great leaders and empires. And those people who were in nations be still had an aspect of individuality, such as traditionalist groups of Jews were targets considered unbritish or Ungerman to many nationalist extremists.
It wasn't the church who called for the genocide of the Jews, not for a long time, but it was the nationalist-racist backdrop that created an extremist view within Christian nations and within a Christian cultural narrative.
So in the posts religion promoted the normality of hating/blaming Jews, more recent nationalism isolated the jews as the enemy within(within Germany, etc.), and when conditions made people vote for extremists, like Hitler, he did what people might have expected. A vast bloodletting.
And Stalin's motivations as far as Atheism does not seem to be correct since there was not an anti-religious stance that existed as a cultural background supporting genocide, nor that of the Jewish people. however, political ideology was key to Lenin's purges, as was the killing of top church officials.
Stalin, who was a gangster for the party, robbing banks to fund the communists, he brought in his old tricks back after he managed to get his hands on some real power. He moved his people into positions of power and when Trotsky was exiled he purged the party over and over, purged the red army too, and broke anyone or anything that got in his way, as he did as a crook before the red revolution of 1917. And creating and maintaining this nation of fear in the 30s was key to his safety in power.
He was still a moderate Christian by some accounts, being raised one, but clearly not a good one at best. His true religion was Himself, he was a communist in name but a narcissist accord to psychological reports, he didn't get off on pain like a psychopath but he seems to have been a sociopath, not dissimilar to Hitler in that respect.
I hope that clarifies things.


[In response to this uninteresting post from Facebook.] 

At no point is any mainstream Atheist seriously suggesting . . .

A common trait amongst many people is to paint the enemy as these evil doers, horrid humans, but often it is false.  As far as Atheists and sceptics it is false to judge all by whichever troll you've been messed around by online.  Equally, one must not jump to conclusions.  The position of many is to build on ignorance, which is a poor foundation to say the least.  From a position of ignorance and a belief in knowledge, the arrogant form serious opinions, and the validity of which will be, by definition, in error.

In my experience, although it is amusing to me, I have witnessed many nonsensical claims.  Some were trolling, but many are so messed up that they believe in these irrational points.  These range from claims of a political alignment, such as saying all Atheists are big government supporters, even though many are libertarian.  Or that all atheists are liberal, some really really are not liberal.  Some believe that Atheists are communists or fascists or Nazis, etc.  No proof that all are, nor that most are, nor that you, personally, agree with those ideologies.

Some claims are that we Atheists want to ban religion, that we want atheist governments, that churches will be destroyed and bibles burnt.  Of the sum of western Atheists, a small proportion may want to do that, mostly sad cases on the internet, many of whom are after attention and offer anti-intellectual arguments for their extremism.  We Atheists, the average non-believers of any title or stripe, we do not seek such things out.  We don't want religion and government to mingle, we believe we are all better off letting believers live with their choices and not being dictated to by other believers or by those who lack belief in religion and the supernatural.  If you don't break the law then there is no real problem we will have, if you aren't trying to manipulate politics by telling your flock how to vote then we'll respect you are far more.

At the worst, the extreme end of everyday Atheism says you shouldn't be able to have tax free status or that you should earn your status through good deeds.  I would be far happier to see the very rich church do more soup kitchens for the homeless and elderly to earn a tax status, and I would love to see the money grabbing cult leaders get jail time or get hit with a big tax bill.  If you're a good church ad you help people, do good for goddness sake, nothing would change, but televangelists would suffer a tax bill.  This doesn't sound extreme to me.  

Now, one thing I wish to bring up is the repeated claim by believing New Age Spiritualists that I want to put them in camps.  I have never said I want to, I do not want to, no mainstream atheist says as much, and it wouldn't help to deconvert magical thinking pseudoreligious nutcases anyway.  And, for goodness sake can't we have a discussion about the evidence without most believers employing fallacies all the time.  I know experience is important to you, as might be stories from others or holy texts, but religious and spiritual people need to know how untrue their evidence claims are.  You do not know how deceptive you're being.

Lastly, I just want to make clear that most Atheists are moderate, they enjoy sports, entertainment, raising their families, socialising, comunity, and many other things that you probably enjoy.  They just don't buy into the god claim because of the lack of evidence for the claim and many rival claims that are equally as nonfalsiable.  So we don't know you're right, we don't know you're wrong either, but that's true of all other gods and magical beings and superadvanced alien beliefs, you can't prove a negative. 

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