That's not at all what Marx said. (I have read the communist manifesto, was part of a BS sociology of the 3rd world class where every answer as to why the 3rd world sucked was the US.)
In fact i'd argue that the Fair Tax would have a good chance of leading to a communist state in a reactionary move.
What Final fan states is fine as well. Even if it's an income tax, if it accurately taxes wealth level what does it matter?