People think they have taken quite an extraordinarily bold step forward when they have rid themselves of belief in hereditary monarchy and swear by the democratic republic. In reality, however, the state is nothing but a machine for the oppression of one class by another, and indeed in the democratic republic no less than in the monarchy.
Friedrich EngelsPeople have learned by bitter experience that the "European fraternal union of peoples" cannot be achieved by mere phrases and pious wishes, but only by profound revolutions and bloody struggles; they have learned that the question is not that of a fraternal union of all European peoples under a single republican flag, but of an alliance of the revolutionary peoples against the counter-revolutionary peoples, an alliance which comes into being not on paper, but only on the battlefield.
Friedrich Engels