> The 18th amendment was added to the constitution not by some legislative need, but to make a politicized statement where another amendment to the constitution would be required to overturn it (the 21st in this case).

That's not really the case. At the time of the 18th amendment's adoption the prevailing legal interpretation of the Commerce Clause was that Congress lacked the power to regulate intrastate trade. So Congress could have prohibited the sale of alcohol across state lines, but could not prohibit the sale of alcohol within the boundaries of a state, and certainly could not have prohibited its production. It wasn't until 1942, in a reaction to Roosevelt's court packing scheme, when the Supreme Court reversed its interpretation and ruled that Congress does have the power to regulate intrastate economic activity (i.e., the production of a good that is not necessarily sold), giving us the modern legal interpretation of the Commerce Clause.

>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.

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.

The Constitutional provenance for the FAA is pretty good. It at least falls under the Commerce Clause. Flying from New York to LA is interstate, and it's commerce.

And what about flying from New York to Albany, or flying a quadcopter in your back yard?