Mill wrote “On Liberty” with his dingbat wife and published it in a fit of grief when she died suddenly. It is the antithesis of everything Locke stood for. Any state that followed Mill's design would rapidly descend into brutal tyranny, something he never considered because he assumed that tyranny was obsolete in the 19th century! Locke's designed the liberal state precisely to defeat the tyranny that Mill's thought would enable.
Of course law and morality must remain distinct from one another (see famous HLR exchange between Professors H.L.A Hart and Lon Fuller). But that doesn't begin to suggest that they can or should remain separate. They can't. Morality precedes law; nearly all laws have a moral foundation. That's as it should and must be. Deal with it. The quote you offer up misses the point of this discussion by a country mile.
Once it is settled that any production of a commodity is subject to federal regulation on the theory that it affects interstate commerce in that commodity (and that was settled decades ago) there is no basis in constitutional theory for supposing that the federal government shouldn't reinforce society's moral judgments about drug production, sales and abuse. You don't limit government by trying to get it out of the business of maintaining society's moral standards. On the contrary you expand it.
The left is deliberately attacking those standards to tear society down and build utopia on the ruins. Any effort to remove legal support for them just plays into the left’s hands, which is what libertarians routinely do. When the moral standards all fall and society comes apart at the seams the result won't be liberty. It will be a totalitarian state. That's what following Mill will net you
...Roe v Wade was predicated on the possibility of a women crossing State lines to get an abortion, constituting interstate commerce, thus giving the Feds the power to "regulate"(legalize) abortion nation wide.
Your statement supports this government action, or at least supports its right to take this action.
So your statement is foolish and will be proven to be more so as the goverment uses this FDR packed court decision in Wickard to control more and more of your life.
Is punishing the pot smoker worth it to you?