History Question: The 16th Amendment

The text of the amendment reads as follows:

“The 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.”

It’s my understanding that this amendment was passed because of a case declaring individual income taxes unconstitutional as a form of direct tax, which was prohibited until the passage of the 16th Amendment.

What was the reasoning for the two latter clauses? …“without apportionment…” and “without regard to any census…”

The original constitution had this language:

Art. 1, Sec. 9

Article I, Section 2 of the Constitution says (in part):

Article I, Section 9 says:

So it’s not that direct taxes were unconstitutional before the passage of the 16th amendment. It’s that any direct taxes had to be apportioned to the states in proportion to the census. The 16th amendment allowed the federal government to collect direct taxes in order to fund itself.

In other words, it would have been 100% constitutional if congress had passed a law which calculated the average income of an average citizen, multiplied that number by 10%, and then multiplied that amount by the number of people in each state (as determined by the latest census) and required each state to fork over that total amount of money each year*. But for congress to pass a law requiring each individual citizen to calculate 10% of their income and hand over that amount was unconstitutional, until the 16th Amendment was passed.

*I wonder if the states would have been free to use whatever method they wanted to collect the money from their own citizens. For example, if the states had opted to take 10% of everyone’s income in their own state and pass it on to the feds, would that have been constitutional?

IIRC, this is all hypothetical because congress chose not to enact any taxes along the lines of “$20 per head” (or some dollar amount calculated to be 10% of the average person’s income) even though it would have been legal for them to do so. Our current income tax system, where each person pays a different amount (even different percentages) was prohibited by Article 1 Section 2.