It's not vague at all. Wealth inequality in the US is so bad that the statement is true with pretty much any reasonable interpretation. The top quantiles of t

It's not vague at all. Wealth inequality in the US is so bad that the statement is true with pretty much any reasonable interpretation. The top quantiles of the population (10%, 1%, 0.1%, billionaires) are paying less taxes than they should in a fair system; and that statement becomes increasingly illustrative of the situation the smaller and richer the quantile you choose is. The fact that wealth inequality is _accellerating_ should be enough to tell you that the taxation system is unfair towards the poorer end.