If in the sequel their interests turn out to be uninteresting and their power turns out to be impotence, either this is the fault of dangerous sophists, who split the indivisible people into different hostile camps, or the army was too brutalized and deluded to understand that the pure goals of democracy were best for it too, or a mistake in one detail of implementation has wrecked the whole plan, or indeed an unforeseen accident has frustrated the game this time. In each case the democrat emerges as spotless from the most shameful defeat as he was innocent when he went into it, fresh in his conviction that he must inevitably be victorious, taking the view that conditions must ripen to meet his requirements, rather than that he and his party must abandon their old standpoint.

From Marx’s 18 Brumaire: https://www.marxists.org/archive/marx/works/1852/18th-brumaire/ch03.htm