Choice holds a great deal of responsibility. Responsibility is the ability to choose for oneself what is right or wrong, something that can only be learned through experience. Experience does not mean that a person should try everything, but that he should know enough about himself and his life to make the decision that is right for him when he reaches a crossroad. If he decides to go ahead and take drugs, then that is the choice that he believes is best befitting his lifestyle and his future. We cannot judge the decision as right or wrong because that would be applying our values and our perceptions to someone else.
Value judgments obscure the true problem.
The reason drugs are illegal is not because they are bad for you and not because the government cares if you have a tummy ache. It is because the people who vote have a general interest in keeping a functional society in which their workers remain efficient producers and live in their communities undisturbed. If the entire middle class were to get high every weekend, the work week wouldn't be very productive. People pay to live in neighborhoods that offer them the certain illusion that they seek, whether it be the fast-paced metropolitan area that suits today's modern man or the quiet, clean community that's just dandy to raise Beaver Cleaver in. If you come strolling along, eating your happy-time brownies as you contemplate why all these people seem really bummed, you've just shattered their illusion, and they can't get their money back any more.