"Many other drugs fit the hellish scenario you're depicting but that's those drugs, not marijuana."
It's a proven fact that Marijuana has psychoactive and physiological effects. Along with a skewed (or one sided) change in perception and mood, the most common short-term physical and neurological effects include increased heart rate, lowered blood pressure, impairment of short-term and working memory, psychomotor coordination, and concentration. Long-term effects are less clear, but many drug users started out just using pot.
Not every person that smokes pot will move on to heavier drugs, but many drug addicts started out with pot. It's a fact.
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