"I don't get it why Bush was so hostile towards a commission?
Things he doens't want to get known to the public?"

Why doesn't Bush want an independent body to investigate the CIA? Other than the political firestorm it would create, you mean?
Everyone knows that CIA is corrupt and "more importantly" incompetent. So what would this commission do other than point to the obvious & generate tons of news content? Bush thinks he can solve the problem by making the homeland security agency- there are a numbers of ways of "looking at this". Rather than speculate, I'm willing to wait and see what the President does- hopefully he will do what's right, opposed to what is the easiest. Kissinger is *good* choice if you don't want a independent body investigating the CIA- it was a easy choice.