Bush and Blair: Francis and the talking mule?

Tony Blair appears to be a highly intelligent, articulate, and open-minded leader of the Labor Party. Bush, on the other hand, seems dull-witted, closed minded, and a bumbling oaf not only in his public speaking but his foreign and domestic policies as well. So why has the infinitely superior Blair followed Bush into this disastrous morass that is Iraq?

"Francis the Talking Mule" was a fifties moves on the lines of "Mr. Ed," where a bumbling man is led around by a mule very much his intellectual superior. In both cases the mule and the horse are dependent on their intellectual inferiors, Francis and Wilbur. So how did Blair become dependent on Bush, which would prove to be Blair's undoing?