I can tell this is an issue which is really close to you

It must be rough watching your students struggle with so many issues day after day.
I am not seeing that Disneybama (or anyone else for that matter) is saying they are "letting" their kids smoke pot--only that they would not consider it as big of a deal as many other things a teen could do wrong.
Anyway, no I am not okay with any smoking of cigarettes because they are so highly addictive and all cigarette smoke has a carcinogenic effect. However, there are plenty of other things that I am okay with my kids using in safe ways but not in an extreme manner. For example, I teach my children that a glass or two of alcohol over the course of an evening is safe and perfectly okay--but that drinking to the point of being sick, blacking out, making bad choices that one would not make sober, etc is not okay (and is in fact very bad for one's health). Another example is as simple as soda: I teach my kids that a glass of soda a few times a week is fine, but drinking a 2 liter bottle a day is terrible for one's health (diabetes, obesity and tooth decay being the big issues there).
With most EVERYTHING in life moderation and balance is important--I think denying that would cause MY children to not take me seriously.
Well, thanks for trying to answer but I am still confused. I must not be expressing myself well.
I agree that I do not want my child addicted to any drug (legal or not) or abusing them in any way (using to the point of being sick, unable to make good decisions, etc even once).
However, you seem to go back and forth with WHY you are so heavily opposed to marijuana. For several posts your emphasis was on it is illegal (and for some reason you seem to have a bigger issue with illegal use of a substance which is never legal than illegal use of an age controlled substance--unless I am misinterpreting things

). At other times, your concern seem to be the dangers of the drug (specifically as it relates to HEAVY users who are predisposed to bi-polar or schizophrenia).
So I guess I am curious what is your overriding concern and why?
It seem to me like that is comparing apples to oranges. It should be more like this:
the vast majority of people who drink a few (1-3) drinks 2-3 times a week over a course of an evening have no ill effects from this. The same is likely true for the vast majority of people who smoke a few (1-3 also?) joints 2-3 times over the course of an evening.
People who are predisposed to alcoholism (family history) or depression are much more likely to become alcoholics if they ever start drinking and need to be hyper aware of the possibility of over use OR abstain all together. Likewise, people with a predisposition to bi-polar or schizophrenia are more likely to have issues if they become heavy used of pot and should there fore also watch carefully or abstain altogether. Many predisposed people (in either case) may not know they carry this genetic marker--thus everyone should be careful not to overuse and to seek treatment immediately if they find they are feeling compelled to do so.
While quite a lot of people do drink and drive without ill effect MANY times such behaviour results in deadly consequences (often to innocent bystanders) and thus this action should never happen--the same is true for driving high.
In other words--comparing MODERATE use of one substance to MODERATE use of the other makes some sense, but comparing moderate use of one to heavy use of the other is just silly (since both have similar effects at moderate versus high levels).