There is the political infighting aspect, but there may be a whole lot more to this than Dems v. Pubs.
See this 1996 policy analysis (long) by the CATO Institute discussing the transition of the CIA from a security espionage body to an economic espionage body after the Cold War and how its economic focus obscured real security threats such as the rise of, among other things, privatization of terrorism by a guy named bin Laden (written in 1996!).
http://www.cato.org/pubs/pas/pa-265.html
Add to that the economic espionage competition between the CIA, French DGSE, Chinese and Russian intelligence agencies, and it's easy to see how an ally in economic espionage could become an adversary in the war on terrorism. Like someone else said on this or another thread, follow the money.
Fast forward to today, and it's as if there are two CIAs and they are trying to kill each other, and Bush needs one of them more than the other.
In fact, he has shifted the focus of the CIA away from the economic and toward terrorism, which would seem to pit a whole host of CIA persons and their international pals (certain Saudi princes, Chinese gov/biz people, etc.) against the administration's objectives.
This may add some more perspective to:
The Gorelick wall - why the CIA would want to prevent domestic security from getting in the way of external economic espionage activities and relationships (e.g. China, Saudis, and others)
Lack of strong security intelligence leading up to the Iraq War.
The Niger yellowcake incident in which a bias toward the economic espionage battle (CIA v. DGSE) undercut what should have been a more diligent security espionage exercise.
The manipulation of the MSM by certain CIA persons and advocates - through leaks and access - to protect their economic interests.
I hope Fitzgerald's investigation can bring some of the CIA's mishandlings to light.