kenyon,
You make a good point. I supported Bush's action in Afganistan, and was pleased to see the Taliban--protectors of bin Laden--toppled so quickly and easily. But that action did not characterise the Bush doctrine, nor get us to the sorry state we are in today.
Rather, it was the Bush administration's insistence on "democratizing" Afganistan, and imposing regime change on the rest of the Middle East. I am all in favor of democracy, and am not one of those who believes that that part of the world is too backward, or something, to be democratised. But imposing a regime at the point of an American gun and then giving it a democratic veneer via elections (a policy Hitch lauds, even now) is a recipe for failure.
Obama is now having to deal with the consequences of that failure in both Afganistan and Iraq. Wisely, he placed Iraq squarely on Bush and the Republicans. Unwisely, he chose in his election campain to champion Afganistan. He, in effect, made our military occcupation of that country his ward. It will be the greatest threat to the success of his presidency.
Hitch heatedly denies parallels with Vietnam, because such parallels point to the failure of policies he vigorously supports. But in Vietnam, too, we tried (unsuccessfully, needless to say) to impose a political regime and then legitimize it as "democratic". And it is difficult to ignore the similarities between the political positions of Obama and Johnson, both of whom inherited a war from their predecessors and, for reasons that are difficult for me to comprehend, made it their own.