Is a Progressive Tax Constitutional?

So much has been made of wealthier citizens paying their "fair share."  Much of the argument against this sort of rhetoric has focused on why we shouldn't raise taxes on the highest tax bracket, or why we shouldn't create another tax bracket.  But one argument that is missing is whether or not such a system of taxation is legal at all. I don't intend to go into a history of progressive taxation (the colonial Puritans used one, too) or of the income tax and the 16th Amendment.  These are irrelevant to the question: Is it just for the government to protect a greater proportion of property of one class than that of another? Under our current system, one man may earn $1 from manufacturing a product and be taxed 25 cents of that profit, while another man may make a similar product of better quality, earn $2 from his industry and genius, and be taxed $1 from the profit.  Does the latter person receive equal protection of the laws? The 14th Amendment states that...(Read Full Article)