An interesting column by John Fund about the flat tax:

High Taxes Wither Away -
Former communist countries lead the way in abandoning progressivity

Envy and the lust for the political control that complicated tax regimes can provide are powerful motivations to keep progressive tax systems in place. Karl Marx in 'The Communist Manifesto' was among the first to call for 'a heavy progressive or graduated income tax' at a time when a flat rate was the norm in advanced countries. He listed it as second in the list of priorities for a new society based on the class struggle.

It is therefore ironic that every country that has adopted the flat tax is a former communist nation--except Hong Kong, the modern originator of the concept, which has seen its new communist rulers retain the flat tax as a centerpiece of its economic policies.

Of course, that's fine for those countries that haven't spent centuries devising an incredibly complex and devious tax code, but for us in the U.S., well, just imagine what throwing all those accountants and tax lawyers out of work would do to our economy.