“Marijuana legalization does not result in an increase of teen use. And for that matter, it doesn’t result in massive changes in the level of adult use either?”

It has always been my contention that the American public, or any public for that matter, has a finite desire to get high. Adding another drug to the mix will NOT cause people to get high more. What adding another drug will do is dilute the use of other drugs. Legalizing marijuana will replace some other, infinitely more dangerous drug use, leading to a net REDUCTION in the harm caused by those others.

Given that very little harm of any kind is caused by marijuana, the degree to which people replace tobacco and alcohol with marijuana will be the degree to which harm caused by legal drugs is reduced. If we could shift ALL tobacco and alcohol use to marijuana (a pipe dream), 98% of the harm caused by all legal recreational drugs will be eliminated. If we could shift just 50% (actually possible), given current alcohol and tovbacco-related mortality, at least 200K lives a year could be saved, in the US alone.

Legalization may not result in “massive changes in the level of adult use,” but there is every good reason to believe that it SHOULD, and that it would ge better, in a variety of ways, if it DID.