Oh, so now you admit there is a problem after all, do you? As one who began by asking such uninformed questions you seem to have answered your own stupid questions yourself.
You should try reading your links: "The study team points out that these associations do not prove cannabis use causes other substance abuse problems."
That just says that it is not true in every instance as this team designed their study (don't do much science, do you?), but the trend of the association of cannabis with being the "gateway drug" to harder stuff and accelerated abuse of still other substances is something which has been well documented for many years and long suspected and that is what the article is about.
While you picked your nose feverishly looking for any excuse - any justification for your stupid position, you evidently missed this:
"Olfson and colleagues analyzed survey responses from a nationally representative sample of U.S. adults interviewed in 2001-2002 and again in 2004-2005. More than 34,650 people responded, almost evenly split among men and women, with a mean age of about 45.
In the first survey, 1,279 individuals reported using cannabis. Three years later, that was linked to a nearly three times higher rate of abusing alcohol compared to people who didn't use cannabis in the first survey. The risk of abusing other drugs or being dependent on tobacco was twice as high, and the risk of having a cannabis abuse disorder by the second survey was nine times higher."
