Every President since Nixon could have done this but the science wasn't there. If you want to blame W then go for it. Obama was considered more enlightened but that's not true.
As far as the medical aspect yeah, weed is bad. Now there are a LOT of active substances in MJ. For medical purposes we don't need all of them. The endocannabinoid system is not as well understood as the endogenous opioids, however we have done work with animals and limited human studies which show that a shotgun is not needed to treat most conditions. The appropriate cannabinoid for this girl has not shown to be a problem at the doses used.
BTW, you know I'm a NY state certified practitoner in medical cannabis, right?