Yes. It is true that people have "claimed" the CSA to be unconstitutional. People have also "claimed" that there is man-made global warming, too.
Is the unconstitutionality of Roe v Wade - or Obamacare - also merely a "claim"?
Clearly false - any goods interdicted during a transfer across a state border have thereby been proven to be distributed interstate.
Correct. But only during the instant of the transfer. Goods on either side of the state border would be legal as there is no way to identify the origin of those goods. Which was the point of the finding.
Patent nonsense - find a vehicle full of pot with CO plates and registered in CO being driven by a CO resident in a neighboring state and you have plenty of ways to identify the origin of that pot.
Purely speculative, as no attempt had been made before or since to control interstate traffic without instrastate control.
It was attempted with alcohol. The 1913 Webb-Kenyon Act made it a violation of federal law to ship an intoxicating beverage interstate. It failed. Miserably.
According to President Nixon's National Commission on Marihuana and Drug Abuse, "The lack of federal enforcement rendered the statute [the Webb-Kenyon Act] virtually meaningless."
Make that: no substantive attempt had been made before or since to control interstate traffic without instrastate control.
So it was on a lark that they underwent the process of ratification by three-quarters of the states?
No. The Anti-Saloon League insisted on a constitutional amendment, believing it would be harder to overturn by a weak-willed populace having second thoughts.
Do you have any evidence that this was their reason? I've looked and can't find any.
Keep in mind, Jefferson banned the sale of alcohol to the Indian tribes without an amendment.
No help for you there - regulating commerce with the Indian tribes is a federal power explicitly granted by Article I Section 8.
Given that the U.S. Supreme Court has ruled both constitutional, yes.
"Patent nonsense - find a vehicle full of pot with CO plates and registered in CO being driven by a CO resident in a neighboring state and you have plenty of ways to identify the origin of that pot."
None that would hold up in court under your definition of the law. Unless the vehicle was observed crossing the state line, there is no crime.
"Make that: no substantive attempt had been made before or since to control interstate traffic without instrastate control."
A substantive attempt. Which would mean federal agents patrolling the state borders of all 50 states. When they can't even protect our southern border.
Well, I suppose we could do it your way. I don't think you'd like it, though.
"Do you have any evidence that this was their reason? I've looked and can't find any."
"An amendment to the Constitution obviously appealed to temperance reformers more than a federal statute banning liquor. A simple congressional majority could adopt a statute but, with the shift of a relatively few votes, could likewise topple one. Drys feared that an ordinary law would be in constant danger of being overturned owing to pressure from liquor industry interests or the growing population of liquor-using immigrants. A constitutional amendment, on the other hand, though more difficult to achieve, would be impervious to change. Their reform would not only have been adopted, the Anti-Saloon League reasoned, but would be protected from future human weakness and backsliding."
-- http://www.druglibrary.org/schaffer/history/rnp/RNP1.html
Your turn. Do you have any evidence that a constitutional amendment was required? I've looked and can't find any.
"No help for you there - regulating commerce with the Indian tribes is a federal power explicitly granted by Article I Section 8."
Yes. But the same clause gives the same power to regulate commerce with foreign nations and among the states.