Nepal, Sept. 30 -- The Olympic 100-metre final is about to start. The crowd roars at the sound of the starting gun. The sprinters are off. But, after 30 metres, the frontrunners slow down, as if in solidarity with the laggards. They have not chosen to do so, but new rules set strict limits on the maximum distance separating the winner from the last-place finisher.

Conservative opponents of income and wealth redistribution have this kind of analogy in mind when they lament the 'politics of envy'. They envision the rich as sprinters that do-gooders want to slow down by law and through punitive taxes.

But life is not the Olympics, where talent and training determine an athlete's performance. It's more like a Roman arena in which well-armed...