Communism:

The term communism stands for a permanently socially just and free future society and was coined in the 19th century. According to Lorenz von Stein, the French revolutionary François Noël Babeuf was the first communist (cf. also Conspiracy of Equals). The best-known representative of communism was Karl Marx (1818-1883). According to the theory of Marx and his close companion Friedrich Engels (1820-1895), communism could only develop out of capitalism, an economic order in which the capitalist class and the working class (proletariat) faced each other as opponents (class struggle), through a revolutionary transitional society (dictatorship of the proletariat). During this rule of the working class, private ownership of the means of production and the accompanying exploitation would be abolished. In the Manifesto of the Communist Party as well as in the "Demands of the Communist Party in Germany", Marx and Engels call for nationalisation. In the preface to the English edition of the Communist Manifesto of 1888, Engels later modified the relationship to the state and mere nationalisation: "In view of the immense further development of great industry since 1848 and the improved and grown organisation of the working class which has accompanied it, in view of the practical experiences, first of the February Revolution and even more so of the Paris Commune, where for the first time the proletariat held political power for two months, today this programme is in places obsolete. Namely, the Commune has given proof that the working class cannot simply take possession of the ready-made state machine and set it in motion for its own purposes." (Friedrich Engels, MEW 21, p. 358)

Fascism:

A definition of "fascism" is difficult, since neither the term itself says anything about its nature (see above) nor did most European movements of the interwar period, which are generally described as fascist, use this word at all - unlike almost all communist parties and regimes, which preferred to call themselves communist.

What fascism is or should be has been determined primarily by its opponents, who have developed theories of or about fascism. Since the 1920s, there has been an intense debate about fascism as a comprehensive generic term that is intended not only to explain the movement and dictatorship led by Mussolini, but also to characterise similar organisations and regimes in other European states. Empirical research has primarily focused on identifying structural core elements of fascism.

An overarching (generic) concept of fascism that encompasses the regimes in Italy, the Nazi state and Japan that existed until the end of the Second World War is controversial in historical research. Some historians want to limit the term to Italy. Others, such as Bernd Martin, consider "fascism" a generic term only for the "movement phase":

"Fascism as a superordinate generic term is therefore suitable at best for the movement phases of the three genuinely developed, commonly called fascisms in Germany, Italy and Japan. As a comprehensive term for the regime phases, on the other hand, the expression does not carry and cannot do justice to the completely different ways in which power was secured. It would therefore better correspond to the historical reality as well as the historical self-understanding of the regimes in Berlin, Rome and Tokyo at the time to abandon the hackneyed term fascism."

Robert O. Paxton describes fascism as a "form of political behaviour". This, he says, is characterised "by an obsessive preoccupation with the decline, humiliation or victimisation of a community, and by a compensatory cult of unity, strength and purity." In addition, there is a "mass party of determined militant nationalists" that collaborates with traditional elites and abolishes democratic freedoms. Internal cleansing and external expansion are to be achieved "with violence transfigured as redemptive".

Fascism researchers such as Roger Griffin, for example, who start from a generic concept of fascism, target the ideological core of fascism:

"Fascism is a political ideology whose mythical core, in its various permutations, is a palingenetic form of populist ultra-nationalism." The American political scientist Paul Gottfried advocates a restrictedly generic concept of fascism: he calls fascist movements and, to a lesser extent, regimes that resembled Italian fascism: As a movement, though not necessarily as a regime, it is held together by a synthetic, changeable ideology that also borrows from the left, especially in its appreciation of revolutionary violence. In this, fascist movements differ from those of the traditional right, with which Gottfried nevertheless sees a certain affinity, for example, with regard to the attitude towards identity politics and hierarchies. The ideological affinity with German National Socialism, on the other hand, is only weakly pronounced. The concept of fascism is mainly applicable to the Mediterranean region and the interwar period. It does not apply to developing dictatorships in Third World countries. Gottfried also rejects the application to "everything that the speaker finds deeply repulsive".

French psychoanalyst Janine Chasseguet-Smirgel and German social scientist Samuel Salzborn argue that subsuming National Socialism under the concept of fascism would remove the core of its essence, namely racial politics and the Holocaust, from the field of vision. In this perspective, the Nazi regime appears as "a very banal dictatorship", not unlike those in Italy, Franco's Spain or Pinochet's Chile. This rationalises the incomprehensible extermination of the Jews and is ultimately a strategy of refusing to remember and deflecting guilt.

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