Who is "one"?
To the decriminalizer's mind, "one" is a twentysomething college graduate with extensive life experience, a supportive family and ample amounts of demonstrated personal responsibility who decides to try a substance for his own amusement.
In the real world, "one" is a poorly-supervised twelve year old with no judgment, poor impulse control, acting under peer pressure with no guidance from wiser people who have his best interests at heart.
Who "one" is matters.
ok replace one with your and they with you
Since teens report that they can get pot more easily than beer or cigarettes, it looks like the most effective way to keep pot out of teens' hands is to legalize it for adults - so sellers have an incentive not to sell to kids (namely, the loss of their legal adult sales).
12 year olds aren’t allowed to use alchohol or cigarettes, either.), let alone buy pornography, see R movies unaccompanied, have sex, drive cars. Why wouldn’t we assume marijuana or anything else would work like that, as well? Go back to argument school.