> i think you are not mentioning meth and heroin, despite them being on the RAND report from 2012 (one may suspect that order/rank may have morphed significantly since then), because the conversation around legalization around them would be an immensely unpopular sell in the US.

Heroin, mostly, comes from Asia, so I did segment a little there. In particular, a lot of heroin comes from Afghanistan, specifically, and American interventions there may have contributed to the opioid crisis. See e.g.: https://www.bbc.com/news/world-us-canada-47861444

Really the post was just too long and I was tired of writing. Opioids will indeed be another problem we have to deal with.

In the case of methamphetamine, there is some hope of substitution with less dangerous drugs like amphetamine, methylphenidate, et cetera. One of the biggest reasons people start using meth is that it's cheaper than other drugs; it's by far the easiest for chemists to make. It's heavily ingrained in various "party" subcultures for this reason, and also features in stories of rural poverty. But that also means that even a strikingly different (hopefully safer) drug could potentially take its place, if it were stimulating and pro-social. In that case we have no appeal to tradition; we have to confront the question of whether "party drugs" can have a place in legal society, which is another matter entirely.

Luckily, the market for methamphetamine is significantly smaller than that for marijuana or cocaine according to the RAND report, and I think this is because demand for meth, which we might call the "ramen noodles" of drugs, is more price-sensitive than other drugs. If the power of cartels is reduced by decriminalization efforts targeting the marijuana and cocaine markets, the price of meth may not be able to rise so easily without impacting demand.