Muman, I wish you wouldn't defend Marijuana use. It has destroyed some of my close friends' lives. It has absolutely caused changes in their mental capabilities. I am not talking about casual use... I am talking about non-stop use from teen years to now in their late 30's. Its very depressing when I see how they have slowly morphed from being sharp-minded to mentally confused; scatterbrained individuals.
One friend specifically told me that he thinks it has caused brain damage, and he is currently seeking help for it. Its a shame that in the past, there werent long-term studies to prove this correlation, but they are finally proving it now, and I will gladly copy and paste the studies if you want me to.
That doesnt mean I think it is lethal, or that it is as dangerous as hard-core drugs. And of course I am for medicinal use of Marijuana, assuming its legitimate.