As we have already seen, after 1815, 1918 and 1945 the Europeans took up similar positions with regard to Russia. There is also a certain parallelism between the situations which came into being in Europe in those years, although most historians tend rather to emphasise the differences than to point out the similarities. In 1815, 1918 and 1945, however, it was important for contemporaries that Russia had functioned as an indispensable ally in a major war fought by a number of European states against another European country which had tried to acquire for itself a dominant position in Europe. Each time this danger was averted by the allied victory, and each time there followed a period in which Russia, although she had made great sacrifices in every one of these wars to save Europe, was seen as the principal threat to the restored European balance of power. In 1918 there was no great fear, as after 1815 and 1945, of military invasion, but rather for the overthrow of the European social structure from within. The reaction to this threat was almost always fierce, frequently extremely exaggerated and sometimes hysterical. This vehemence is understandable. The takeover of power by the Bolsheviks suddenly made it possible to link the old spectre of an aggressive, expansionary and barbaric Russia with the existing abhorrence of socialism. The clichés of antisocialist propaganda, which in 1918 could also boast a fairly long historical tradition, could therefore be used.