From Nouriel Roubini in an interview with Hard Assets Investor:

OPEC can manage prices marginally. The only supplier that has excess capacity that can use it to stabilize oil prices is Saudi Arabia. But once oil is above $80 like it is now, ETF demand, options demand, speculative demand, these can easily push it to above $100.

I would say that if there were a reason we had the global recession last year, it wasn't just Lehman or the subprime mortgage problem; it was that when oil went to $145. That was a major, real trade shock negative, and a real disposable-income shock for the U.S., Europe, Japan, China and all the other oil-importing and commodity-importing nations around the world. That kept the world in recession when oil was at $145. Now, I feel that oil at $100 is going to tip the world into a double-dip recession.

...[L]ast year, when oil went to $145, half the world, like emerging markets, was growing very fast. But today, with the global economic collapse...

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