Interesting. I just finished Tale of Two Cities a little bit ago, and the oppressed peasantry certainly used their "moral superiority" to do their share of butchery.
A very salient observation. The French Revolution, which occurred at about the same time as the American Revolution, had a completely different outcome, due, in part, to the fact that the American Revolution was based on Lockeian principles, while the French Revolution was rooted in the false egalitarianism and class envy that later came to define Marx.