Flat tax

The idea of a flat tax is appealing.  Putting it into practice is much tougher.  Every change involved will have unintended consequences that must be addressed.  First, if you start taxing at the first dollar of income most low income families will see huge tax increases.  If not, how much income do you exclude?  Making the exclusion a significant amount raises the flat rate to 15-20%, again, higher than most people's rate now. 

What about deductions?  Taxing charitable contribution deductions harms charities, not taxpayers.  Taxing mortgage interest drives down the value of houses even farther.  Taxing retirement contributions decreases savings and increases dependence on Social Security.  Taxing municipal interest increases costs for roads, bridges, sewers, and so on. 

Like I said, I like the idea of a flat tax but I just don't think we can get there from where we are without major economic disruptions.  The best we can hope for is to get rid of the deductions and subsidies that make the least sense, flatten rates by as much as we can, and take another bite at the apple in a few years.