Comment by roenxi

There are a couple of key phrases in politics that get used because there is no actual justification. "Fair" is one of them. It is impossible to achieve fairness in the tax system under any circumstances, it is always taking from someone who - from the fact that it isn't voluntary - we can assume quite likely disagrees with how the money is about to be used. Taxes are fundamentally arbitrary.

So in practice, if "fair" is used in politics the appropriate reading is often as a euphemism for "I think we have the numbers to push this interpretation of the world on people; it'll be good for us".