On the economics of petroleum, once you massively invest in renewable fuels, in a sense you're betting that crude prices are going to remain very high. Nobody really knows what's going to happen. The price of crude oil today is $70. That $70 is at least $20 of speculation and fear of what could happen here and what could happen there, and probably $40 would reflect the current supply and demand tightness. It could go down or it could go up.
If you look at a world where Iran is not a threat or a perceived threat, if you look at a world where the Middle East becomes quieter, and if you look at a world where some conservation finally takes place—and I'm going to keep repeating that even if nobody asks me a question on it, because nobody talks about that, by the way—then crude oil's going to go down to $30 or $35.
If you look at a world where the threats increase, the fear factor keeps on having those effects, and no real conservation takes place, then you're going to have crude at $75 to $100. That's the range. A lot of it is within human control.
I don't know what it's going to be, but it's certain that with crude at $35, subsidization of other fuels is going to be a lot more expensive for governments or taxpayers than it would be if crude oil were at $70. But at $70, it already has inconveniences.
You have to choose the scenario for the future, and it's not easy. It's an added complexity to the policy that you're going to be defining. The policy will have to change or adjust to future petroleum prices, because the economics change completely.