The Communist Manifesto leads directly to the "dictatorial regimes of the 20th century". The Communist Manifesto is not founded in any reality (psychological, political, economic), and as it is applied but fails to bring the promised benefits as it is completely ungrounded in reality, it also encourages the leaders to come to the conclusion that the only reason this can be is that the people aren't trying hard enough. This requires a stronger centralized rule to fix the problem and force the people to comply, but strengthening the centralized rule just causes more problems because centralized rule doesn't work, and it certainly doesn't work with the horrifyingly wrong Communist economic model. This causes yet more centralized power to be amassed and yet more crackdowns, until it crumbles under its own weight.

It's utterly predictable, mostly because we've seen so many try to apply it and fail in exactly the same way each time. We're well past the point where we can say the Communist Manifesto directly leads to dictatorial regimes. I will recant this statement when someone manages to apply it without turning into a dictatorial regime, but don't hold your breath for that.