My high school education took place in the 1970s, and as a result I had a pretty solid understanding of Communism - and its evils. I knew about both the Russian and Chinese versions; and these were expounded alongside National Socialism in Germany as variations on the theme of totalitarianism - three ideologies with many similarities and lesser distinctions.
George Orwell has been by-far the most influential advocate of this analysis; but it was the Western norm up into the 1970s.
But in contrast, the next generations were taught very little indeed
about Communism. The 'totalitarian' analytic category was not used. Instead both school and culture hammered home, again and again, an
indictment of the Nationalsozialistische Deutsche Arbeiterpartei (NSDAP; in
English, National Socialist Workers Party of Germany) as the unique and greatest evil of world history.
However NSDAP is
nearly-always abbreviated to Nazi, presumably to de-emphasise its roots in
Socialism and its Communist-like pro-worker stance. And nowadays the
NSDAP is treated as an "extreme Right Wing" party.
What was not made clear - even up to the 1970s - was that these examples (Russia, Germany, China) were all among the rare instances in human history of explicitly atheist states. Because this unfying atheism was seldom mentioned, and because the post-mid-sixties generation took secularism for granted; its significance was missed. (This particular neglect has - of course - continued.)
And because atheism as the core and unifying feature of the twentieth century totalitarianisms was missed; the seeds of our current falsehood were sown.
It used to be said (from the late 1940s and until the middle 1970s) that Communism and National Socialism were examples of extremes meeting. The idea was that Communism and National Socialism were opposites, Left and Right, but at the extremes Left and Right circle around and join-up.
This is a devastating error. In fact, Communist and Nazi are merely variations on the same basic ideology, which is Leftism.
National Socialism is merely Communism moderated by Nationalism (i.e. Nazis were moderate Communists); because in the middle twentieth century Communism was ideologically inter-nationalist (as with their theme song).
More specifically, National Socialism (and indeed, also the earlier Italian Fascism under Mussolini, and the later Falangist-atheist/ Roman Catholic alliance of Franco in Spain) was a reaction-against the internationalism and socially-destructive extremity of Communism.
Because after the Russian Revolution there was a widespread (and apparently justified) fear that Communism would spread across Europe. National Socialism in Germany was a Socialist Workers party, exactly the same as Communism (and appealing to a similar proletarian base); but was nationalist and patriotic, which enabled the different classes to work together under the revolutionary new arragements.
Rather than the attempt being made, as in the USSR, to exterminate the bourgeoisie and the ex-aristocrats; instead the NSDAP imposed a new ruling class of 'lower class' party members (mostly derived from the non-gentry, 'blue-collar' middle class, in practice: e.g. Hitler had been a Non-Commissioned Officer). However, (unlike Communism) although aristocratic titles and privileges were abolished; the ex-Junker nobility, Professors, writers and artists, clerks and schoolteachers etc were all welcome to join the national ('workers') effort; so long as they endorsed the new ideology. Apparently, most of them accepted.
Thus National Socialism was far more effective and efficient than 'pure'/ extreme Communism, since it succeeded in mobilizing a far greater proportion of the population - across all classes; because it repudiated some of the insane inversions of Communism, and also because the NSDAP replaced religion with an intense, supernaturalistic, ritually and symbolically-supported cult of The Fuhrer.
The hatred of Communists for Nazis is therefore the hatred of the ideological purist for the moderate pragmatist. On the other side; the hostility of Nazis to Communism was itself the springboard of their success with both the German workers and the ruling class.
The traditional German nobility and gentry correctly perceived that (in the short/medium-term, anyway) - when the range of possible choice had been reduced to Nazi or Communist, they would be much better-off under the NSDAP than Communism.
Anyway; it can be seen that the recent global totalitarian coup was made possible by the decades of neglect and disinformation concerning Communism, and the misrepresentation of Nazis as 'extreme Right Wing' -- rather than an understanding of the nature of generic atheist totalitarianism that encompasses both.
(Part of this was also a false representation of the essence of the Nazi system as being anti-semitism; whereas this was mostly a peculiarity of Hitler himself, and not-at-all intrinsic to the NSDAP system of government.)
Furthermore, the lack of of comprehension concerning the atheist roots of totalitarianism has affected the opposition to mainstream post-middle-1960s New Leftism - because there is a false belief in 'a non-religious Right'.
Whereas there never has been, and never can be, a non-religious Right; and all purported examples of non-religious Right are actually merely (more or less) moderate forms of Leftism; just like the NSDAP.
All forms of political atheism are 1. Leftist, and 2. Totalitarian. The only thing which disguises this is social inertia; and as older (religious-reared) generations die-out, all possible secular societies will move Left towards the extreme of psychotic Communism.
Thus, since the entire West (and developed nations) have been atheist for some decades - all-without-exception are now (and for the past few months) extreme Leftist and under totalitarian rule.
The only genuine opposition to totalitarianism is therefore from those who wish to put religion at the centre of the political system: those who regard religion as more important than politics (or anything else).
And the only legitimate dispute among those who oppose Leftism is: Which Religion?