He's correct.
"Congress shall have power to lay and collect taxes on incomes, from whatever source derived, without apportionment among the several States, and without regard to any census or enumeration." -Amendment XVI
"That the authority conferred upon Congress by 8 of article 1 'to lay and collect taxes, duties, imposts and excises' is exhaustive and embraces every conceivable power of taxation has never been questioned, or, if it has, has been so often authoritatively declared as to render it necessary only to state the doctrine. And it has also never been questioned from the foundation, without stopping presently to determine under which of the separate headings the power was properly to be classed, that there was authority given, as the part was included in the whole, to lay and collect income taxes"
Brushaber v. Union Pacific Railroad 240 U.S. 1 (1916)
"... the provisions of the 16th Amendment conferred no new power of taxation, but simply prohibited the previous complete and plenary power of income taxation possessed by Congress from the beginning from being taken out of the category of indirect taxation to which it inherently belonged."
Stanton v. Baltic Mining 240 U.S. 103 (1916)
"The Sixteenth Amendment must be construed in connection with the taxing clauses of the original Constitution and the effect attributed to them before the amendment was adopted."
Eisner v. Macomber 252 U.S. 189 (1920)
In other words, the 16th Amendment did not give Congress any new authority whatsoever. The limited and plenary taxing power of Congress is noted in Article I Section 8 of the U.S. Constitution and no where else. No Amendment can grant a power that is unconstitutional anyway.
As I said, jurisdiction is key here. If Congress has always been able to tax income... who exactly would be the target of such an imposition? Might it be those engaged in matters concerning the function of the federal government as a foreign agent to the states? If a foreign business wishes to do business in the U.S., they must utilize the services of the federal government and are thus subject to a tax upon the domestic income produced. If a U.S. citizen contracts with a foreign entity and generates foreign income while residing abroad, they are also subject to a tax upon that income.
So, regardless of all the ratification arguments, the 16th Amendment does not affect the vast majority of Americans at all. If you want to understand the 16th Amendment, read the Brushaber case online at FindLaw.com. Follow up with other significant cases such as Doyle, Eisner, and Merchant's Loan and Trust. However, never forget that the basic legal principles don't change.... jurisdiction is paramount.
The 16th Amendment and the income tax (as written) are 100% Constitutional. An individual's lack of knowledge does not make these out to be something they are not. However, ignorance has allowed the income tax to be applied incorrectly with proponents even using the 16th as justification... those proponents being equally ignorant.
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