Comment by dataflow

Isn't it illegal in the entire US? The question doesn't seem to be whether you can obtain it legally, but how many laws you'd rather break in the process, and how much trace you'd like to leave behind. I imagine the illegal vendors are less likely to leave a discoverable trace (that could affect your future background checks etc.) than the "legal" vendors, which itself is an incentive to obtain it illegally even when it's cheaper and safer and easier to obtain less-illegally right next door.

Which basically means the US hasn't really tried legalizing it at all.

(Not advocating for any position here, just commenting on the facts.)