As explained by Nobel Laureate Joseph Stiglitz:
SPIEGEL: Before the invasion of Iraq, the US administration said the best way to keep oil prices in check is a short and successful war. A barrel was at $25 at that time, and now it's over $60. What of this increase is due to Iraq?Stiglitz is talking about oil fields were the oil must be pumped out of thick sands, for example. For more background, see peakoil.com.
Stiglitz: In our analysis about the cost of war, we only assumed a modest $5 to $10 caused by the war. We wanted to keep our study conservative, so no one would dispute our numbers, and no one did. But I believe that's a vast underestimation of the true cost.
SPIEGEL: But why? China and India are increasing their demand, real global growth has been going on. This is driving the prices.
Stiglitz: When demand rises so does supply -- that's how markets usually work. Now we're seeing that demand for oil is rising but we're not getting a commensurate increase in supply. And there's a simple answer, it's Iraq. But it's not just because it production has been down.
SPIEGEL: Why else?
Stiglitz: The Middle East is the lowest cost producer in the world. They can produce oil for $10, $15 or $20 a barrel. Now we have the technology to produce oil elsewhere for $35 to $45. But who wants to develop fields or invest in new technologies elsewhere if they know that in five years' time, the Middle East may be supplying oil at previous prices?
SPIEGEL: In other words, were peace and stability re-established in the Middle East, the oil price would be back to maybe $25, despite the huge global hunger for energy?