>OK, but we passed a constitutional amendment saying the opposite

Which amendment is that? The 21st repealing prohibition did not make any value statements on whether prohibition was ever good policy, it merely repeals the amendment banning alcohol.

> and the so-called "War on Drugs" operates in defiance of the spirit of that amendment.

There is no "spirit of [the] amendment". It repealed a ban on alcohol. Alcohol was undeniably an extreme social ill before prohibition.