I never told you that for the first time. We aren't talking about taxation, we're talking about regulating commerce. Specifically we're talking about the federal government regulating the internal commerce of the States.
Tell me again about the section of the Constitution that makes drug use a unenfringable right?
The 14th makes clear that governments cannot deprive people of life, liberty, or property without due process of law. - In other words, laws must be both written & enforced using Constitutional due process.
Justice Harlan on due process:
"-- The full scope of the liberty guaranteed by the Due Process Clause `cannot be found in or limited by the precise terms of the specific guarantees elsewhere provided in the Constitution.
This `liberty´ is not a series of isolated points pricked out in terms of the taking of property; the freedom of speech, press, and religion; the right to keep and bear arms; the freedom from unreasonable searches and seizures; and so on.
It is a rational continuum which, broadly speaking, includes a freedom from all substantial arbitrary impositions and purposeless restraints, . . . "
Poe v. Ullman, supra, 367 U.S. at 543, 81 S.Ct., at 1777
Thus we see that prohibitory laws violate due process, since they declare you guilty by mere possession of the 'sinful/illegal' object.