They were the only ones who were able to get to the place they wanted work in the amount of time available.
When I worked at Pratt Whitney we competed with GE and Rolls, but we got no bid contracts because of logistics.
Same thing here. Halliburton was ready and in place.
And contrary to rats claims, Cheney stepped down so there would be no conflict of interest claims by the dems.
Cheney sold all his retirement investments in the company to try to satisfy the rats. Did it help? Heck no.