For longterm US interests, Bush did a great thing.
We (US firms in US dollars) manage Iraqi and Afghan (caspian) oil.
The US has set up permanent bases in the region.
The US has ensured the dollar will still remain relevant.
The cost has been 5 trillion dollars, borrowed from China mostly.
The gain? Well, iraq alone has $50 to 75 trill worth of saleable oil. Caspian oil is 10 at worst and estimated to be more.
The bush admin did a necessary thing. They said in 2000 they'd do it - they wrote the PNAC document (cheney, Rummy, Jeb, wolfy, bolton and others) detailing plans to control arabian oil and positioning. Then they did it - exactly as they said they would.
Problem now is that some Americans (rich ones) have been getting fat and living large off the tax cuts for the wealthy, and a dem will bring that back to earth.