[gozur88]

>However, the U.S. constitution does talk at length about both congress who can write laws (like the laws banning hard drugs)

No. This is all the constitution has to say on the subject of regulating commerce:

"The Congress shall have Power... To regulate Commerce with foreign Nations, and among the several States, and with the Indian Tribes;"

The constitution gives Congress the power to regulate interstate commerce. It does not give Congress the power to regulate anything within a state's borders, which was why alcohol could not have been banned without the 18th amendment.

The reason we have federal drug laws is the courts have been willing to simply ignore the text of the document for political expediency. But this didn't start happening (in the case of the commerce clause, anyway) until 1942 with Wickard v Filburn.

[logfromblammo]

And that doesn't even account for lexical drift. At the time, "regulate" meant to moderate, normalize, or make uniform, a sense that is more accurately captured now in the word "regularize". The clause, at the time, probably meant that Congress was to have the power to force all states follow uniform rules with respect to trade.

The intent was probably to protect other states from circumstances wherein California could determine the emissions requirements of their cars and Texas could determine the content of their textbooks.

The clause, as intended, would have allowed the Uniform Commercial Code to be federal law instead of identical legislation passed by all 50 states. But it would not have allowed for the aforementioned political expediency.