Dunno about Bush's wanting to turn A-stan into anything but a launching pad to go after bin Laden. That's the pretense under which we went in to begin with so soon after 9/11. A sidebar attraction was getting rid of the Taliban, which has proved a difficult nut to crack.
I'd say the end game, from Zero's dithering perspective, is to hang on long enough to pretend that something got accomplished, then exit declaring "victory". Puts Petraeus in a very awkward position, not that he isn't accustomed to that. In fact, Petraeus is the element that keeps the whole shooting match from becoming another Vietnam - as a student of history, he knows all too well what happened with Westmoreland.
No question that Diem's assassination mired us deeper into 'Nam, but it's debatable as to how much. Since he got offed shortly before JFK himself was offed, it could be argued that LBJ's irascible nature was the real catalyst - after he won the 1964 elections, of course, which most definitely was a priority.
There's a lot of backchannel shit we're not privy to, natcherly, and while Zero is already on record with wagging his mocha-flavored finger at Karzai for corruption during the latest "election" (kinda hard to really use that word, since it denotes that the people did the talking, but anyway), it's pointless to continue that practice.
In essence, Zero's waltzing with Karzai and if Zero had some balls (which he does not), he'd find a way to ratchet up the diplomatic pressure -- not that that would do any good whatsoever.
The diplomats are accustomed to dirty dealing, backstabbing, and other methods of "working with your coalition partners".
I guess the part that sticks in my craw is that he's so blatant about sucking I'manutjob's crank, in addition to Zero's. Tell you the truth, I'm kinda surprised to see that Karzai's still alive. He's pissed off a lot of people on both sides of the fence and, like Pusharraf in P-stan, he's been in the center of crosshairs for a very long time.