"the timing of it definitely lines up for sure" For the most part. There were a few local bans going back to the early 1900's but most of those were on the southern border and they were mostly just an excuse to harass Mexicans but the big push came later.
I have heard good things about kratom but I have never gotten around to trying it. I have some knee pain so it might help. I think you might be right. If it has real health benefits then it is a threat to the pharmaceutical companies in the same way that weed is. If I was a little more knowledgeable about the substance I might write about but I really have focused most of my experimentation with psychedelics and cannabis.
All that synthetic stuff is pretty bad from what I understand but it really is a problem that they created. The traditional illegal drugs tend to be better at giving people what they are after and are usually safer. I said it in the other comment but no one buys spice if they can smoke weed.
RE: Needing New Enemies: Salvia, Kratom, and Opposing the Modern Drug War