All he really has to do is manipulate the petroleum market, say by selling off the Strategic Oil Reserve. Of course, that would be if Bush's goal was popularity. If his goal were to make huge oil profits for himself and his pals, at any cost, he would, well, do exactly what he's doing:
Invade and shut down one of his biggest foreign competitors (Iraq).
Threaten another one with Regime change: Venezuela.
Threaten another one with Regime change: Iran.
Talk pretty about alternative energy, while slashing the budget for alternative energy research.
Allow one of the major centers for petroleum extraction and refining to be submerged and destroyed: New Orleans.
Threaten to drill in a pristine wilderness, creating a false sense that oil is the only energy and it is so scarce that desperate measures are justified.
Subsidize the oil companies to the tune of many billions of dollars in tax breaks.
