It makes sense if you care about both harm and liberty though.

We've already decided alcohol is fine from a liberty perspective, so if the argument against cannabis is from a harm perspective, and cannabis is less harmful than alcohol, then cannabis should be fine too.

I'm not sure that we (in the US) decided alcohol was fine from a liberty perspective, I think it was more the social consequences of Prohibition appeared to some to outweigh the evils it was fighting and to be somewhat ineffective to boot. For something as socially acceptable as drinking, it probably would have been better to take the sort of tack that was taken against cigarettes: increasingly high taxation, relentless educational campaigns beginning in childhood, advertising bans, regulation, bans on flavors etc., culminating decades later in total bans like what is now planned in some countries.

"disincentivising", also known as "war on drugs" is making criminals more rich and police more corrupt.

"dry laws" have also mostly resulted in proliferation of illegal alcohol sales and criminal groups dealing with that.

perhaps harm reduction should be dealt with in a different way than prohibition and use of force.

A society determines which harmful substances (and its effects on the individual and the society) it tolerates and how. Alcohol is in Germany tolerated (more than in the US) and it is also a huge legal business.

I'm for tolerating both alcohol and cannabis, but without mass marketing (ads, ...).

One struggle we face is the large inflow of other drugs, the resulting damage (for example from crack) currently from south America, the import of crime from there and the use of the drug business of legal cannabis business to expand their other drug business.

> is making criminals more rich and police more corrupt.

And youngsters who smoke weed in the streets learn to hate cops. Which may or may not be a bad thing.

you're correct, but prohibition when not largly accepted socially have bad consequences.