I am doubtful that our government could come up with a responsible plan to do so. However, I am of the opinion that if America was to really make a positive mark towards its own self sovereignty, it would consider legalizing all drugs and then going further in doing so.
The American population is overburdened with the selfish use of drugs by individuals now especially in the form of "expendable children" that end up in the foster care system or otherwise as just one example. The burdens on all government funded programs for what is basically an "indulgence" is just not sensible. However, in light of the present government, "sensible" is just not an adjective I could even throw at them hope to stick.
However, if there was a change in the law. The law having very strong and clear consequences for not being able to handle your drug use. These rules would be more or less an "assumption of your own peril" law. Also, I believe like the drinking age, the drug use age should be 21 not 18, because even at 21, most young people do not have the social responsibility for themselves and are not capable of backing up their own actions. The law should also be strong for minors and distinquish itself from what would be considered everyday law. These laws are meant to both be punative and self-supportive as there should be both a penalty and a financial aspect to it. It should be firm and without flexibility because we are talking about something that is an "indulgence" and not a necessity. Also, alcohol should be added to this same set of laws.
Along with the law aspect, the "assume your own peril" would extend to health insurance, medical care and there would be high taxes placed on any and all drugs. A person would have to have identity just like a person has to have a driver's license to get alcohol, the same for all drugs. But in this, there would be a strong taking of personal liberty for drug users then as there would be a "monthly" and even a "weekly" limit on what a person can buy of each drug. Also, a person who is more or less "licensed" cannot share their stuff with someone else, anyone found to be under the influence without the licensing will be subject to a strong law whereby both a fine and a one year stipulation of the "assume your own risk" would be applied to their insurability status.
Anyone who does drugs in America would be entitled to a controlled health care system. The heavy taxes levied on each legalized drug would be used to pay for this program. There would also be limits on care especially when care seems to be obsessive and when a person no longer seems to have control in their life, their decisions would be made for them to a degree. In this, a person would lose the priveledge of being legally able to consume any drug material at all until a minimum of a year passes and there is a physical examination done at the applicant's expense to regain this status.
I believe it would create a new level of prosperity but with such a thing, you cannot trust that everyone will just be cool and light up a doobie and get a little high and that be that. Not everyone stops at a wee bit of inebriation, euphoria or hallucination. The law should be prohibitive but not invasive. IN that if you should legally get you head messed up, you are within your legal right until it offends the safety and well being of another. This is also in following with Dr. Albert Fisher's treatment of psychadelic drugs, especially LSD where he definitely set some rules for use in that a person had to have both set and setting before beginning "the trip". In China, there are "opium dens" that are talked about where people basically go to "get wasted". These are not very responsible dwellings but they do have themselves set away from the general public.
The same thing should be done for prostitution where both the prostitute and the "john" would have their health and well being protected more than the way things are now. The system we have and the ridiculous "war on drugs" are still a means by which the wealthy gain power and influence in the otherwise "civil world" leaving in their wake the mess that others have to clean up. Franklin Delano Roosevelt, the Delano part of the family was responsible for shipping heroin throughout Asia as a means of social control. The priveledge in America to use recreational drugs has to come at a clear cost and eliminate the criminal and irresponsible element that does not clean up the mess it makes. It is a rather tall order really as I am not a conspiracy theorist, but I do believe that a great deal of the power and wealth in this nation feeds off the misery and depravity which drives and fuels the current system of drugs. Even the leaders of our country seem to have a romance with the methods of incarceration and social control that the law has in place now. However, it is a hemmoraging artery that in the end is swept into more money from the government to throw a square of toilet tissue to in order to somehow stop it.