What's more, Vladmir_M referenced Hitler in an argument that something bad wouldn't be repeated until Hitler. That's not hypothetical, that references a terrible thing in the technically true rhetorical construct of "X is/was the worst thing since/until Y" where Y is/was worse than X, possibly by orders of magnitude, but the brain associates X and Y as similar regardless, in a way that is inappropriate.

Every totalitarian terror state has been consciously inspired by the French Revolution and Red Terror - Marx invokes the red terror as a good idea, though perhaps not carried out with sufficient thoroughness.

While "X was the worst thing until Y" can inappropriately associate X and Y, there are in this case many connections and similarities between X and Y.

Critics of the French Revolution foresaw twentieth century totalitarianism in its actions and ideology:

Joseph de Maistre foretold:

The people are told by their masters:

You believe that you don't want this law, but we assure you that you do. If you dare reject it we shall shoot you down in order to punish you for not wanting what you do want.

and then they do so

Since reference to Hitler automatically provokes irrationality, I would have said, and come to think of it I did say, that the French revolution prefigured the totalitarian terror regimes of the twentieth century.