I know you posted to ohioWfan...but, I can answer your question.
President Bush did NOT appoint this ISG...a Congressman (R) put this forward as legislation...and Congress passed it...and they appointed the committee.
Bush had nothing to do with it.
But lets say you are the President of the United States. The Leader of the Free World. Head of the Grand Old Party.
Give me a plausible explanation as to why you would just stand by and do nothing while defeatists in your own party picked out members of an advisory group to undermine your efforts to win in Iraq?
If Bush is so politically weak or just deaf that he can't see that he is giving away his ability to gain support for any policy which might win in Iraq, how screwed are we? How long will it be before he is holding press conferences like Clinton did in 1995 trying to convince the press corp that he is still relevant?
To give this a little context, lets go back to the last commission. The 9/11 commission. Clinton put one of his own attorneys on there along with his political appointee from the DOJ to ensure that his name didn't get muddied. He had Sandy Burglar stealing documents to cover his tracks. And in contrast, who on the GOP side can you really claim that Bush had in there as a political infighter for him? The GOP side was filled with people neither you or I could either remember or wouldn't appoint to a Christmas decorating committee. Where was the political calculations in this and aren't we still getting beat up by these jello sherriffs today because we didn't do it right the first time?
Maybe I'm just not above engaging in politics to achieve our goals. And maybe I'm alone in that cuz it doesn't appear outwardly that Bush is willing to engage in politics and he (and us) continually suffer for it.