Earlier quoted context omitted.
So you cap income tax at 2%. Congratulations you just tripled property tax and made sales tax 20%. Taxes are like wackamole. You can't just limit 1 tiny piece and expect anything to change. Furthermore you can't just lower the total take unless you want to explain where the cut is coming from. Less school funding? Less roads? Less police? Less Army? More debt?
My understanding is that the federal government cannot impose a property tax, without just distributing it to the states by population. My reading of the commerce clause is that they couldn't impose a sales tax on in-state commerce. So it's not like these went away after they gained the power to assess an income tax: they were never an option. As a general rule, you could remove any government agency created with the…
(1) The commerce clause is a grant of power, not a limit. It's indisputable that the commerce clause does not authorize a tax on in-state commerce, but it doesn't prohibit one, either. So we need to look beyond the commerce clause and ask if a federal sales tax is authorized anywhere else.
(2) The dollar value of sales is income, derived from sales. The 16th Amendment gives Congress the authority to "lay and collect taxes on income, from whatever source derived, without apportionment among the several states". Therefore, a federal tax on the gross income from sales is authorized by the 16th Amendment.
(3) But, wait, we don't even need the 16th Amendment. There's a special word for a tax on sales of goods -- its called an "excise". And its an express Constitutional power of Congress even before any amendments, in the Tax and Spending Clause, with the restriction that they must be uniform throughout the United States.