It really is voodoo

Here we go again.

When Ronald Reagan ran for president in 1980, he promised to cut taxes in what seemed, at the time, a magical way. Tax revenue would go up, not down, he said, as the economy boomed in response to lower rates.

Since then, supply-side economics, as it was called — first with derision but then as a label embraced by its supporters — has become a central tenet of Republican political and economic thinking. That’s despite the fact that the big supply-side tax cuts of the 1980s and the 2000s did not work out as advertised, as even most supporters acknowledge.

But advocates see broader economic benefits from lowering tax rates, which is one of the reasons the concept has reappeared as a point of contention in this year’s election campaign, in an amended form.

“What really happens is that the economy grows more vigorously when you lower tax rates,” said Kevin Hassett, an adviser to the presumptive Republican nominee, John McCain, and the director for economic policy studies at the conservative American Enterprise Institute. “It is beyond the reach of economic science to explain precisely why that happens, but it does.”

Even with a growing economy, however, the promised boon in tax revenue never materialized. Arthur B. Laffer, the renowned proponent of supply-side economics, still holds that tax revenues “rise dramatically” when tax rates are cut.

It's really incredible how conservative ideology, repeatedly shot to pieces and proven illogical and wrong, simply never dies.