"Even JFK realized that lowering tax rates spurs economic growth, which benefits citizens across income categories. "
You know, it's funny you say that. The top marginal rate under Clinton (wherein we had the largest peacetime economic expansion in US history) was up to nearly 40%, after Reagan/Bush dropped it from 50 down to 28 (later up to 31 91-92 when Bush realized the economy was slumping).
In the case of Kennedy the top rate was 91%, inherited from FDR 20 years earlier. In 64 the rate went down to 77% -- but Kennedy was dead by then. We used to tax the living shit out of the rich. They have it much easier now.
All these numbers are marginal rates -- that is to say, the percent you pay on the rest of your income when you pass into the highest income bracket.
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