How can a new administration withdraw from Iraq?

I still believe that there is a last chance to avoid further insanity in the Iraq-crisis; namely thru the UN enforcing resolution 377 “uniting for Peace”, demanding the immediate cessation of hostilities in the area and the subsequent withdrawal of all aggressor forces from Iraqi territory. This followed by a continuation of weapons inspections along with a strong humanitarian/social effort including the posting of UN observers all over Iraq and a huge presence of human rights defenders of some sort. (This would be very much LESS expensive than the current path taken.)

However, at present this scenario seems unlikely. What I’d like to start a discussion about is the following:

Suppose that the war continues and finally leads to the toppling of Saddam Hussein and his regime. According to popular beliefs, some US general is then to lead the occupied territories for an undecided time. The massive contracts for reconstruction etc etc will primarily go to large US corporations, and an eventual end to the occupation may be predicated on some vague measure of stability. Iraq is many times as populous and large as Palestine and thus by necessity much harder to control. Following the Israeli example, crackdowns on “terrorism” can be claimed indefinitely as an argument to stay on and protect “vital American interests”.
(Notably, convenient slurs about terrorism can already be heard from the coalition command when describing those who dare to actively oppose their “liberation”.)

OK – this is truly repulsive and shameful.
But is there later on any credible way a new US administration could withdraw from the occupied territories? Or will the occupation be made permanent through the huge reconstruction contracts, and virtually free access to enormous natural resources for the occupants? Very likely voices would quickly be heard saying that “our boys must not have died in vain” if anyone tried to return Iraq to the Iraqi people.