Orrin Judd takes up the subject here with crash-ax inhand and gives Rationalism more than a flesh wound. He calls upon Weaver, Hume and Oakeshott amongst others to help with the heavy lifting. I rather like his handiwork.
In short: so what if reason is itself irrational and only faith allows us to believe in its utility; faith suffices. In effect he's returned us to the pre-Rational worldview, where reason was a tool that God had given us in order to apprehend Creation. Thus is Reason cut back down to size and Faith returned to primacy.
It can hardly be a coincidence that Rationalism and Intellectualism and the theories they spawned have been far more influential, and destructive, in Descartes's France and on the European continent than they have been in Hume's Anglosphere. Having blindly clung to a metaphysic that was so clearly flawed, it's not surprising that Europeans (and American intellectuals) proved susceptible to the seductive allure of such rationalisms as Darwinism and Marxism, which offered perfectly rational explanations of how the world worked, if only you ignored the fact that we can't know it to be rational or material and that experience demonstrates otherwise. Meanwhile, in England and its former colonies -- but especially in America -- we have generally followed the example of Hume and been skeptical if not utterly hostile towards intellectuals and the claims of Reason. Perhaps that alone explains why there has never been a viable Communist party, nevermind a Marxist government in the Anglo-Saxon world and why Christianity remains so strong and Darwinism has fared so poorly in the States.
The post covers quite some ground but is worth the time.