Keith Hennessey goes to a lot of trouble to make an irrelevant argument:

I assume that some who read this will react automatically with disbelief and sarcasm. They think they know that President Bush is unintelligent because, after all, everyone knows that. They will assume that I am wrong, or blinded by loyalty, or lying. They are certain that they are smarter than George Bush.

I ask you simply to consider the possibility that I’m right, that he is smarter than you.

As I’ve said on other occasions, intelligence is no guarantee of good judgment, relevant specialized knowledge, or executive competence. A politician can have above-average intelligence and still support disastrous and ill-conceived policies. We see this happen with remarkable frequency. Indeed, a smart politician lacking in humility may think that he has can do things that less ambitious people would never contemplate trying. By many measures, Condi Rice is very smart, but she did a horrible job as National Security Adviser, and her tenure as Secretary of State wasn’t very impressive, either. Bush might very well be smarter than most of Hennessey’s students and he might be smarter than many of us, and it wouldn’t change the fact that some of his signature policies were disasters and some brazenly violated established legal and ethical norms. Being smart is no guarantee against moral and ethical failures, and it’s no guarantee of good judgment.

Consider the example of Mitt Romney. Romney is undeniably very intelligent, so much so that he probably falls into the category of “too smart for his own good” when it comes to politics. Whatever else Romney critics said over the years, no one ever doubted that he was very smart. Regardless, the fact that Romney was obviously very bright didn’t change the reality that he a) knew virtually nothing about foreign policy; b) seemed unconcerned that he didn’t know very much about it; c) endorsed a series of reflexively hawkish policies because that was what a conventional Republican nominee was expected to do. In these respects, there was a frightening resemblance between Romney and Bush in their shared overconfidence and ignorance about the world. Romney endorsed misguided foreign policy ideas because he didn’t know much about the subject, didn’t care about it very much, paid it very little attention despite running for president almost continuously for six years, and because these were the ideas that the “experts” he surrounded himself with favored. Romney’s statements on foreign policy during his presidential campaigns confirmed one thing above all, which is that smart people can believe incredibly stupid and foolish things.