Infuriational Imbecility
You could actually make an argument that this is more funny than infuriating, but as someone who's maintained for years that George W. Bush is a walking, talking middle finger in the face of the whole concept of meritocracy, this article by Jacob Weisberg of Slate.com hits me where I live. Here's a li'l taste:

...if "numskull" is an imprecise description of the president, it is not altogether inaccurate. Bush may not have been born stupid, but he has achieved stupidity, and now he wears it as a badge of honor. What makes mocking this president fair as well as funny is that Bush is, or at least once was, capable of learning, reading, and thinking. We know he has discipline and can work hard (at least when the goal is reducing his time for a three-mile run). Instead he chose to coast, for most of his life, on name, charm, good looks, and the easy access to capital afforded by family connections.

The most obvious expression of Bush's choice of ignorance is that, at the age of 57, he knows nothing about policy or history. After years of working as his dad's spear-chucker in Washington, he didn't understand the difference between Medicare and Medicaid, the second- and third-largest federal programs. Well into his plans for invading Iraq, Bush still couldn't get down the distinction between Sunni and Shiite Muslims, the key religious divide in a country he was about to occupy. Though he sometimes carries books for show, he either does not read them or doesn't absorb anything from them.

Again, here's the whole thing.