Lee Harris at TCS Daily makes the case:
Today, no self-respecting conservative wants to be thought stupid, not even by the lunatics on the far left. Yet there are far worse things than looking stupid to others—and one of them is being conned by those who are far cleverer than we are.... The bell curve virtually guarantees that there will always be those who can pull the wool over the eyes of the rest of us, and if we once begin to listen to their spiel, then we find that before we know it we have been taken advantage of....
The stupid conservative, on the other hand, does not look for a higher authority than tradition itself. He is prepared to rest his case simply on traditional authority alone, without seeking to appeal to logic, or reason, or empirical data. For what reason gives, reason can take away....
In a world that absurdly overrates the advantage of sheer brain power, no one wants to be seen as a member in good standing of the stupid party. Yet stupidity has been and will always remain the best defense mechanism against the ordinary conman and the intellectual dreamer, just as Odysseus found that stuffing cotton in his ears was his best defense against beguiling but fatal song of the sirens.
I was originally going to conclude with some pithy jibe, but this seems to me an argument that really speaks for itself.