Your arguments are nonsensical. First you intimate there can't be a problem because no states in the USA have rolled back legalisation of cannabis. Then you use alcohol and tobacco as examples of greater problems that need to be dealt with before worrying about cannabis. Can you tell me which US states have recently rolled back legalisation of alcohol or tobacco? If none of them have, then, by your own logic, they must both be safe. Also, I'm not sure why you think USA legislation should be held up as some kind of shining example to the rest of the world? Look at the ridiculous gun laws and the fact the per capita murder rate in the USA is 20 times that in the UK. That Americans have yet to make the connection suggests a serious lack of insight at best.
The end of your post is the most ridiculous example of whataboutism I've seen recently.