The government already tried prohibition with alcohol. It was a miserable failure. About 1,000 people a year died from bad booze (bathtub gin & moonshine). There were a lot of other problems, organized crime, bribes to police, etc.
Ken Burns had a documentary on that.
https://www.pbs.org/kenburns/prohibi...d-consequences
I support the decriminalization of marijuana. But we would still need to enforce DUI and other related laws if you commit a crime while under the influence.