The Congressmen who are urging an excess-profits tax on the oil industry are making a proposal that is more innovative than they may realize. Major excess-profits taxes have been clamped on U.S. business three times since 1917, but in every case the tax was levied on almost all corporations in order to help pay for a war. Never before has the nation debated imposing an excess-profits tax on a single industry in peacetime.
Previous excess-profits taxes have been justified partly as a way to raise vast amounts of money quickly. Now, practically nobody bothers to talk much about how many dollars an...