So I take it by this statement that you regard the transshipment of drugs from foreign countries as effectively an attack on the populace of the United States. Good, because that's how I see it as well.
But I think the Government has the authority to deal with attacks that come from inside our borders too. The salient point here is that drugs constitute an "attack" against our populace.
Congress has NO authority to regulate trade that occurs within a State.
It isn't "Trade" when it deals with dangerous and illegal banned substances.
The only salient point is that this article deals with INTERNAL intrastate regulation.
The congress has no authority to regulate intrastate commerce. The State laws do that really well.
Drugs are not always an attack, and are meaningless because there is a difference in the Constitution on what can be done between the US States, and actors outside the US.
Don't like it? Change the Constitution, don't ride roughshod over it, allowing things like abortion at the federal level.
I'm greatly heartened that firearms laws and abortion laws are tending back to the State, where those questions belong.
/johnny