That the Nazis were Socialists, that fascism in Germany was Socialist in nature is much more widely understood today than when I was young in the 1950s and perusing the latest New York publisher’s Nazi-centric history of World War II.
In their telling fascism was some sort of weird right-wing, racist cult unto itself with no connection to the Soviet Socialist tyranny. It was the time of the Cold War and the Soviets were too powerful to be treated insensitively (like the violent Muslims today) in addition to the fact that Leftists controlled the publishing industry and had an interest in protecting Socialism’s reputation.
Today, thanks to Google in particular and the Internet in general the connection between the Nazis and the Soviets is much more obvious, in things like their sharing of Poland in 1939. Study the old, once rarely-seen photos of the Nazi and Soviet officers smiling and shaking hands as they prepare to murder the Poles and confiscate their property.
New histories like Timothy Snyder’s Bloodlands likewise underscore the Nazi-Soviet cooperation in the Holocaust. His figures, from the formerly-secret Soviet archives and elsewhere, show the almost six million Jews were among a total of 16 million people murdered by Europe’s two most powerful Socialist regimes.
Leftists can continue to deny the Socialist connections to this appalling genocide all they please. They have always been great deniers of the obvious. But their grip on the public’s understanding of history is loosening steadily. Mercifully.
Via Instapundit.
THE TEXAS SCRIBBLER 
One of the components of that “brotherhood” was the common cultural elements. Both sides hate to talk about that today, but some people remember. Check this out:
http://simplyjews.blogspot.co.il/2009/07/blood-chilling-affinity-or-songs-that.html
Thanks for the link. I remember an old photo of Polish horse cavalry pathetically charging Nazi tanks. Until recently I never saw the photo of Soviet cavalry on white horses parading through Lviv, Poland.