There were only 2 billion people on Earth in 1940 but seemingly at least that many ideologies - every kind of -ism under the sun.
An -ism or ideology can be thought of as the governing presumptions of a Great Civilization or a potential Great Civilization.
(That last sentence was perhaps full of redundancies because as anyone ever heard of a small civilization ?)
In 1940, the most powerful of these -isms were actually scientism, nationalism, capitalism, racism, and imperialism.
But the most rhetorically warring ones , the ones with the most acknowledged supporters, were not them at all.
Rather they were ones called something like Liberalism,Conservatism, Communism, Nazism, Fascism, Democratic Socialism orJapanese Yamato-ism.
In rhetoric, this lot all seemed as different from each other as could possibly be.
However all these the ideologically warring Great Civilizations also saw that the same common international language (advanced modern era science) was the real key to achieving their rhetorically different aims.
So much so that the -ism of scientism ended up ensuring that the tails of these very different ideological dogs all wagged in the same direction.
Now early Modern Era science was not really very 'open-mindedly scientific'.
Scientists back then frequently set out to prove up unstated and largely unconscious assumptions that the scientists had already made about the basics of Reality : philosophy first, empiricism second.
At a time when the number of publishing research-oriented scientists were comparatively few and the history of such activity only a few decades old, it was easy for these pioneering scientists to unconsciously select various tiny aspects of the vast array that is Reality and present them as typical - and so 'proving up' their philosophic thesis.
Today we having millions of publishing scientists and a hundred and fifty years of scientists doing such activity. And now we have the Internet conveying all of this published research instantly and cheaply to all other scientists.
As a result, much more of the complexity of Reality has come to light and this very diversity and complexity, in of itself, has destroyed the belief that human science can quickly and confidently uncover the secrets of Nature.
But none of this was terribly evident in 1940 --- the ism of Scientism ruled , warmly supported by the Left or the Right, across the entire world of Civilizations.
In fact to be a Civilization was to be scientific and to be scientific was to be part of a Civilization.
Since Modern Era Civilization always consisted of imperial dominion over other ("lesser") human beings and since Modern Era Science always consisted of imperial dominion over ("lesser") Nature, the two provided a complete continuum of dominance over other beings and other things.
All the Great Civilizations agreed on the right and need to dominate lesser beings and things - they only differed in who this imperialism was supposed to benefit.
The middle class and deserving working class in democratic imperial civilizations, the working class in socialist and communist imperial civilizations, the Aryans, Romans or Yamato races in the German, Italian and Japanese imperial civilizations.
In all cases, a tiny elite at the top of each great Civilization benefitted the most and suffered the least under any reversals.
One billion people in the world during WWII experienced longterm severe shortages of food - but no member of any ruling class, regardless of the -ism they espoused - anywhere ever went to bed hungry.
Call this a young child's (profound) understanding of what all the -Isms and Great Civilizations and Scientism really meant ...