Your argument that the war was premised on 9-11 is a strawman because no one in the Administration ever claimed Iraq was responsible for 9-11.
Did we mistakenly believe that Saddam had stockpiles of WMD? Yes we did.
Was that belief reasonable and shared by every other major intelligence agency in the world? Yes it was. As a matter of fact, Saddam admitted that he intentionally deceived the world into believing he retained a WMD stockpile and had every intention of resuming his programs once the UN sanctions were eased. Sanction, by the way, that were crumbling in large part due to the corruption in the Oil for Food Program.
The lives lost are a tragedy for every family that lost someone but if you believe the casualties in this war have been excessive you lack historical perspective. The same goes for your concern over the dollar cost.
The exit strategy is now and has been from the beginning a simple one: Victory, defined as the removal of the Ba'athist regime and the creation of a popular government that is able to sustain internal security and stability, defends its borders while being non-threatening to its neighbors and an ally in the war on terror.
I would suggest you look at the latest opinion poll of the Iraqis before you make the assertion that we are not wanted there.