Marijuana is very hard to simply be classed as benign in its effects; however is it a fact that its long term use at a non-abusive rate has less side effects than that "substance" of a higher calibre. In fact there is no hard evidence to suggest that marijuana used by a young adult would have severe side effects physically such as those higher up the substance hierarchy.
There was a very famous study conducted by Dr. Robert Heath, done in the late 1970s in association with Institute of Medicine and the National Academy of Sciences . This experiment was implemented in order to distinguish the effects of marijuana on the brains of four monkeys. The experiment itself was highly scrutinized because of the sample size, failure to control bias and not correctly identifying the normal brain structure of the monkeys used in the trail. The trail indicated that the effect on the monkey's brain was severe and left them "brain damaged". However it was later revealed that the amount of smoke that had been concentrated and funnelled through gasmasks was the equivalent approximately one hundred joints in the period of 5 minutes with little to no oxygen flowing in the masks, this is a dangerous practice. The monkey's brain shut down after 5 minutes, for the obvious reasons. Over the years an actual study was conducted over a human population of users and found absolutely no evidence for brain damage. This includes the 1977 article published in the Journal of the American Medical Association concluding that there was no evidence of brain damage in heavy users of marijuana
Is Marijuana a gateway drug? Absolutely not. The most common misconception of marijuana is that it is a gateway drug leading to many other harder and more dangerous habits, however this is not true. In Holland, the Dutch partially legalized marijuana in the 1970s. Until now hard drug use such as heroin and cocaine have reduced substantially and consistently. If you were to agree with the misconception that marijuana is a gateway drug than you also have to bind this also to alchahol and tobacco. I believe the misconception may be true in the sense that because marijuana is illegal, the efforts in obtaining it are quite minimal, the exposure of other hard drugs becomes apparent as the person selling marijuana in most cases also sell other things.
If marijuana is indeed as potent and dangerous as is being marketed by your leading television network, then why is it that there are no recorded deaths from the use and abuse of marijuana? Logically one would answer that is just does not have that capability and therefore its potency is not an issue.
The main argument which may be pointed out would be that early stages of marijuana use triggers an already existing disposition of the users brain for psychosis or schizophrenia. This is true, however this is true in very young users using repeatedly at a young age which then triggers this mental condition, however this is not an instant effect and does take time, even if that time is only a small frame. But is this argument solid enough to justify the criminalization of marijuana? No. In fact going back to my previous statement in regards to the minimal effort and exposure, is that no drug dealer or marijuana peddler cares too much for the age of their customers and is left to their own discretion. If there was control on the substance I would imagine that the law and social standard or culture that would call for a minimum age of 18 or 21 to be able to buy such things. This is in regards to marijuana only and not higher up the pyramid.
Tobacco is a substance that has many side effects. Prolonged use and abuse of this substance can cause many effects as well as the horrific attacker, Cancer. The prolonged use and abuse of alchahol can also cause very many mental and physical side effects and as tobacco being highly addictive and alchahol only moderately addictive, they never the less are legal.
In conclusion I would have to agree that the effects of marijuana are indeed a benign chain of effects. The initial effects, as well as its long term ones are nothing to be particularly concerned about. If one is concerned about their health and the health of the public than it is in my opinion that the use of tobacco be slowly eradicated from our society as it is one of the leading causes of death in our world today.