This is an excerpt from fairtax.org/flattax. It explains why the flat-tax (HR1040) hurts middle-class America and how the FairTax treats every citizen who spends above the poverty level equally.
Flat tax supporters often emphasize, correctly, that marginal tax rates, rather than average or effective, are the most economically relevant tax rates. It is the marginal tax rate that affects an individual’s decision about what to do.
The FairTax generally has a more positive impact on marginal tax rates than does the flat tax.