Deagolwulf (no relation) talks about socialism and mass-extermination and how the two have been linked at the hip since Dr. Guillotine’s invention.
Once the idea has arisen that all ideas are merely the accompanying shadows of various social classes, groups, races, etc, cast in the light of their fixed interests, then another idea may very well present itself: that the only — or at least the surest, quickest, and most effective — way to get rid of an idea is to get rid of the class, group, race, etc, in whose interest it is said to be an ever-attendant shadow. 
 Socialist intellectuals were the first advocates of mass-extermination as official social policy, conceived as the precondition of progress. As George Watson points out: “In the European century that began in the 1840s, from Engels’s article of 1849 down to the death of Hitler, everyone who advocated genocide called himself a socialist, and no exception has been found.” (George Watson, The Lost Literature of Socialism (Cambridge: The Lutterworth Press, 1998), p.80.) The reader can accept the challenge, and see if he can find an exception.
Plenty more to read there. Get thyself hence and partake thereof.
One other thing Deagolwulf says that we should all agree with: