Most drugs in pure form (and moderation) are not that harmful. Individuals have problems that are allowed to go too far before treatment is started because of the underground nature of drugs.
Take nicotine, in pure form is one of the best drugs. Increased mental acuity, decreased reaction times and sense of well being.
Add creosote, arsnic, cooch grass and the burning agents, deliver in smoke and you have a huge problem.
Most powders and pills problem is the crap it is cut with. Not to mention not realy knowing if it is what you expected / paid for (or if it is the strength you expect).
I for one would rather be in a crowd of stoned people (except for PCP) than drunk people. (from personal experience)
Most of drugs bad name comes from lawyers using it as an excuse. "its not my clients fault because he was high at the time." (He took the drugs, did the crime and now claims to be the victim. Take some responsibility for your actions.)
When I was caught with a bong (pipe), I owned up. Very embarasing to hear later in court "when questioned if the suspect had any cannabis as well he replied "no sir, its my birthday, I was celebrating, I've smoked it all!" "