It’s pretty widely assumed that several recent wars (most obviously those in Iraq and Georgia) have been motivated, in part at least, by the desire to control oil and other valuable resources including natural gas and (one that is close to my heart) water. The other side of the same coin is the idea (again evident in both these cases) that countries with control over valuable resources can use that control to further their own geopolitical ends.
But examples where either of these strategic ideas has been applied with success are thin on the ground to say the least. While I don’t subscribe to simple ideas of “war for oil” in relation to Iraq, it’s pretty clear that one of the many motives for going to war was the desire to put Iraq’s oil under the control of a government friendly to the US (and preferably not so friendly to rivals like France and Russia). The war has been as spectactular a failure in this respect as in many others. With the best part of a trillion dollars already spent and trillions more to come, the US is worse off in the oil market than it has ever been.
On the other side, the oil embargo of 1973 signalled the change from a market dominated by a buyer cartel to one dominated by a seller cartel. But in geopolitical terms it was a disaster. The Israeli occupation arising from the 1967 war, then only six years old, is still almost intact 35 years later (the Egyptians got the Sinai back, but not because they had any oil).
More generally, I suspect that countries wanting oil can’t do better than to buy it at the going price, and that those wanting to maximise the benefits from owning oil would be best off selling it for the same price and using the money to promote their strategic goals (or, more sensibly, investing it in projects like education).
Of course, showing that it’s stupid to go to war over oil doesn’t prove that people won’t do it. Empirical observation gives us plenty of evidence of the fact that people are more than usually stupid when war is concerned. In the early 20th century, Norman Angell’s Great Illusion demolished the idea that modern nations could secure economic benefits by fighting over war and resources. He was proved right in the most appalling way possible: the Great War that began in 1914 led to the ruin of all the parties.