Frantz Fanon, also known as Ibrahim Frantz Fanon wrote in his book, The Wretched of the Earth:
Not long ago Nazism transformed the whole of Europe into a veritable colony
meaning that the techniques pioneered in the colonies of Europe were turned upon Europe itself, culminating in the horrors of the holocaust, mirroring that, of say the Belgian Congo.
[I've asked this question in History.stackExchange but also asked this here as I wan't sure whether this is really a question of History or of Political Philosophy. I err towards the latter. Fanon is classed as a Philosopher on Wikipedia.]
As further evidence, I've read somewhere the philosophers Simone Weil & Hannah Arendt made similar claims.
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It turns out that Aime Cesaire, who taught Frantz Fanon in Martinique at the Lycee Schoelcher in Fort-de-France, published in 1955, when Fanon would have been thirty, Les Discours sur le Colonialism (Discourse on Colonialism) in the French review magazine La Presence Africaine. based in Paris. Fanon published The Wretched of the Earth in 1961. It’s also worth mentioning, given some of the comments I received about both the philosophical content and justification of this question, that this journal was set up by the Senagalese professor of philosophy, Aliune Diop more or less a decade earlier. Cesaire wrote:
Colonisation or civilisation? In dealing with this subject, the commonest curse is to be the dupe in good faith of a collective hypocrisy that cleverly misrepresents problems, the better to legitimise the hateful solutions provided for them ..
To admit once and for all, without flinching at the consequences that the decisive actors here ... [is] the baleful projected shadow of a civilisation which at a certain point in its history, finds itself obliged, for internal reasons, to extend to a world scale the competition of its antagonistic economies...
Pursuing my analysis, I find that hypocrisy is of a recent date: That ... Cortes discovering Mexico from the top of the great teocalli ... did not claim to be a harbinger of a superior order. The slavering apologists came later. that the chief culprit in this domain is Christian pedantry which laid down the dishonest equation: Christianity=civilisation, paganism=savagery; from which could not ensue abominable colonialist and racist consequences, whose victims were to be the Indians, the yellow people and the Negroes.
... each time a Madagascan is tortured, and in France they accept the fact, civilisation acquires another dead weight, a universal regression takes place, a gangrene sets in, a centre of infection begins to spread, and at the end of all these treaties that have been violated, all these lies that have been propagated, all these punitive expeditions that have been tolerated, all these prisoners that have been tied up and interrogated, all these patriots that have been tortured, all this racial pride that has been encouraged, all the boastfulness that has been displayed, a poison has been instilled into the veins of Europe and slowly, but surely, the continent proceeds towards savagery. [emphasis added].
And then one fine day, the bourgeoisie is awakened by a terrific reverse shock: the Gestapos are busy, the prisons fill up, the torturers around the rack invent, refine, discuss.
People are surprised, they are indignant ... and they hide the truth from themselves, that it is barbarism, but the supreme barbarism, the crowning barbarism. That it is Nazism, yes, but before they were its victims, they were its accomplices; that they tolerated Nazism before it was inflicted upon them, that they absolved it, shut their eyes to it, legitimised it, because, until then, it had only been applied to non-European peoples, that they have cultivated that Nazism, that they are responsible for it, and before engulfing the whole of Western, Christian civilisation in its reddened waters, it oozes, trickles and seeps from every crack.
Yes, it would be worthwhile to study it clinically, in detail, the steps taken by Hitler and Hitlerism and to reveal to the very distinguished, very humanistic, very Christian bourgeois of the twentieth century that without his being aware of it, he has a Hitler inside him, that Hitler inhabits him, Hitler is his demon, that if he rails against him, he is being inconsistent, and that, at bottom, what he cannot forgive Hitler for is not crime in itself, the crime against man, it is not the humiliation of man as such, it is the crime against the white man, the humiliation of the white man, and the fact he applied to Europe colonialist procedures which until then had been reserved exclusively for the Arabs of Algeria, the coolies of India and the blacks of Africa ...
I have talked a great deal about Hitler. Because he deserves it. He makes it possible to see things on a large scale and to grasp the fact that capitalist society, at its present stage, is incapable of establishing a concept of the rights of man, just as it has proven incapable of establishing a system of individual ethics. Whether one like it or not, at the end of the blind alley that is Europe. I mean the Europe of Adenauer, Schuman, Bidault and a few others, there is Hitler. At the end of Capitalism, which is eager to outlive its day, there is Hitler. At the end of all formal humanism and philosophical renunciation lies Hitler.
I’ve quoted at length, given, at least in my mind, the importance of the question, and also because he makes the argument that Frantz didn't.