Because despite its medical benefits, pot is still not just illegal, but schedule 1, in the US.<quoted text>
if marijuana cures cancer, why do we still have millions dying every year?
Also, when I say pot cures cancer, I have given the references, which provide all the details you need. There are thousand of cancers, and the benefits have been proved only for 173 forms. In some case it cures completely, in other case it shrink the tumor, etc. Pot can cure some sciatica very efficaciously too. You can find a good cannabis dictionary of all diseases whose cure benefits from pot. Pot seems to have a large spectrum of medical use, because it seems to act at some deep level on the immune system, white cells, etc.
I am not a big fan of pot, but I do care about politicians lying and hiding facts about health (and not just health). This endangers the quality of life, if not life itself, of all those I care about. About cannabis it is beyond any reasonable doubts that they have lie to us since the start.
The illegality of cannabis is just a symptom of a graver problem, a sort of confusion between means and goal in economy, which eventually give the power to the bandits and criminals.