Your certitude is not supported by your ignorance of history:
Prohibition was that generation's war on drugs, and it's not pretty.
The government went to obscene lengths to "discourage drinking": https://www.snopes.com/fact-check/government-poison-10000-am...
And the "voting" was the money'd class, not "the people": https://www.hagley.org/librarynews/prohibition-centennial
Let's not forget how well it funded organized crime, but not nearly to the extent that the current WoD has literally created the drug cartels south of the border.
Moving on to your "observations" of failure. The fact that we literally have a fent crisis nationally shows that the war not only was an abject failure but literally created the fent crisis (cheaper and easier than heroin and easier to smuggle).
As far as the oppression angle, there's plenty of documented history on this issue. For starters there's this: https://www.brennancenter.org/our-work/analysis-opinion/race...
I've lost friends to drugs, my brother died of a heroin overdose and my mother died from complications of alcoholism and smoking. Your simple-minded dismissal of the problem is insulting to their memories and millions of others.
Nobody should be doing fent recreationally, let alone passing out on the street. But if your answer to that problem is "Give the DEA billions of dollars more, and fill our prisons with those moral degnerates" then you are sadly mistaken.