Just because the US made researching cannabis so hard to do that American researchers gave up trying to jump thru all the hoops doesn't mean research didn't go on elsewhere. The Israelis have done extensive research on pot's medicinal properties and it's huge business for them now.
Here in Canada medpot users are the ones that fought and fell to finally get medical status for pot 20 years ago and when the sky didn't fall Trudeau knew he could get the stoners off the couch to vote for him if he promised to legalize and it worked. Again the sky didn't fall.
It has been PROVEN to have many medicinal uses so maybe you just need to read outside of the American sphere of influence to educate yourself. The US is the main reason pot was made illegal in the first place then forced their values on the rest of the world. When alcohol prohibition was being lifted Harry Anslinger was about to be out of a job so needed another demon to fight and picked pot. Very few people other than Mexican farm workers and black jazz musicians even used pot at the time and he was a huge bigot. But then all the fuss about pot made white kids curious so it's use swelled from there making it even more popular than ever.
Until pot prohibition came along there were hundreds of medical formulas containing cannabis at every drug store and the doctors fought long and hard to prevent prohibition but big pharma was just beginning and didn't want the competition.
That is only a couple of the reasons that pot was made illegal in the first place and it was mostly about money and prejudice.
Follow the money! That covers almost everything in our lives that is f'ed up by greedy soulless bastards everywhere.