Whether the "millionaires and billionaires" are actually paying their fair share of taxes is a matter for the electorate to decide. After all, fairness is hardly an objective standard.

Before the modern era, however, the federal tax system was manifestly unfair by any reasonable standard, grossly biased in favor of the well off. Ironically, attempting to fix that unfairness is what has brought us to the present moment, with a federal tax system that is grotesquely complex, often...