Some interesting material on the resurgent windfall profits tax:

Dan Shaviro (NYU):  A Windfall Profits Tax for Oil Companies?:

Is there any decent intellectual defense for a windfall profits tax on oil companies? The standard economics-inflected answer would be no, for the same reason that one might want to let price gougers charge what they like for water in a drought disaster area. The argument is that the high returns encourage them to anticipate and fill demand, bidding the price back down and causing the market to respond to demand shocks much faster than it would otherwise. Thus, in the oil company case, the standard argument would be that windfall profits attract apparently needed extra capacity into the industry.

Nonetheless, a couple of reasonable arguments could be made, in present circumstances, for a windfall profits tax on oil companies….

Tax Foundation:  Oil Company Profits and Tax Collections: Does the U.S. Need a New Windfall Profits Tax?:

This week, the Senate will hold hearings on rising oil and fuel prices and the subsequent record earnings recently posted by U.S. oil companies. Some lawmakers have suggested that these profits are unseemly and, thus, should be subject to a new “windfall profits” tax.

Before rushing to create a new federal tax, lawmakers should ask two questions:

1.  Do oil companies currently pay too little in taxes compared to profits?
2.  What was the effect of the last windfall profits tax enacted in 1980?