The U.S. Social Security levy is widely used by economists to illustrate the irrelevance of legal tax incidence for economic incidence. However, the levy's magnitude in conjunction with an asymmetry in the U.S. federal income tax code make the levy's legal incidence highly relevant for its...

Pure fiscal actions—fiscal actions that leave the money supply unchanged—cannot alter aggregate demand without concomitant support from the monetary sector. At the initial level of output, either the demand for money or the quantity of money demanded must change appropriately....