I don't know if Harpers is considered mainstream, but that they're saying Blood for Oil probably means that's it OK now to state the obvious. The war crime that was the U.S. invasion of Iraq was motivated by many things - oil being among the top three.
The other top motives? Defense of Israel, and George W. Bush's personal desire to be 'great'. In my humble opinion.
On December 3, 2002, well before the March 20, 2003 invasion, Chomsky wrote this:
More generally, the September 11 terrorist atrocities provided an opportunity and pretext to implement long-standing plans to take control of Iraq's immense oil wealth, a central component of the Persian Gulf resources that the State Department, in 1945, described as "a stupendous source of strategic power, and one of the greatest material prizes in world history" (referring specifically to Saudi Arabia, but the intent is more general). US intelligence predicts that these will be of even greater significance in the years ahead. The issue has never been access. The same intelligence analyses anticipate that the US will rely on more secure Atlantic Basin supplies. The same was true after World War II. The US moved quickly to gain control over Gulf resources, but not for its own use; North America was the major producer for decades afterwards, and since then Venezuela has generally been the leading exporter to the US. What matters is control over the "material prize," which funnels enormous wealth to the US in many ways, and the "stupendous source of strategic power," which translates into a lever of “unilateral world domination.”
It's never too late to start reading Chomsky.